{"id":7256,"date":"2013-05-01T08:03:07","date_gmt":"2013-05-01T12:03:07","guid":{"rendered":"https:\/\/www.masterorganicchemistry.com\/?p=7256"},"modified":"2026-04-21T10:45:03","modified_gmt":"2026-04-21T15:45:03","slug":"acetylide-formation-alkylation","status":"publish","type":"post","link":"https:\/\/www.masterorganicchemistry.com\/2013\/05\/01\/acetylide-formation-alkylation\/","title":{"rendered":"Acetylides from Alkynes, And Substitution Reactions of Acetylides"},"content":{"rendered":"<p><strong>Alkylation of acetylides<\/strong><\/p>\n<ul>\n<li>Terminal alkynes have unusually acidic C\u2013H bonds (pK<sub>a<\/sub> 25). Treatment with a strong base such as sodium amide (NaNH<sub>2<\/sub>) gives an <strong>acetylide<\/strong>, the name for the <strong>conjugate base<\/strong> of a terminal alkyne.<\/li>\n<li>Acetylides are more stable than the conjugate bases of alkenes and alkanes due to the fact that the lone pair is held in an <em>sp<\/em>-hybridized orbital which has 50% s-character. Since s-orbitals are held closer to the positively charged nucleus than p-orbitals, the electrons in this orbital are more stable <span style=\"color: #993366;\"><em>(i.e. have less potential energy)<\/em><\/span><\/li>\n<li>Acetylides are strong bases, but can also act as <strong>nucleophiles<\/strong> in nucleophilic substitution reactions (S<sub>N<\/sub>2) with alkyl halides to form substituted acetylenes.<\/li>\n<li>These reactions work best for primary and methyl alkyl halides.<\/li>\n<li>Attempts to form C-C bonds via S<sub>N<\/sub>2 reactions with secondary alkyl halides almost always results in elimination (E2) instead, due to the high basicity of the acetylide ion.<\/li>\n<li>The reaction of acetylides with alkyl halides one of the <strong>most important reactions you will learn in first semester organic chemistry<\/strong> because it provides a versatile way of <strong>forming C-C bonds<\/strong> and <strong>extending the carbon chain<\/strong>.<\/li>\n<li>This reaction is therefore a key entry point in planning the <strong>synthesis\u00a0<\/strong>of various molecules, especially since the resulting alkynes can be hydrogenated to alkanes (and partially hydrogenated to alkenes, as we&#8217;ll soon see). [<span style=\"color: #993366;\"><em>See article &#8211; <a style=\"color: #993366;\" href=\"https:\/\/www.masterorganicchemistry.com\/2011\/08\/19\/lindlars-catalyst-partial-cis-reduction\/\">Partial Hydrogenation of Alkynes to cis-Alkenes With Lindlar&#8217;s Catalyst<\/a><\/em><\/span>]<\/li>\n<\/ul>\n<p><img fetchpriority=\"high\" decoding=\"async\" class=\"alignnone wp-image-35941\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2013\/05\/0-summary-alkylation-of-alkyynes-through-deprotonation-and-reaction-with-alkyl-halides.gif\" alt=\"summary- alkylation of alkyynes through deprotonation and reaction with alkyl halides\" width=\"640\" height=\"401\" \/><\/a><\/p>\n<p><strong>Table of Contents<\/strong><\/p>\n<ol>\n<li style=\"list-style-type: none;\">\n<ol>\n<li><a href=\"#one\">Terminal Alkynes Are Acidic!<\/a><\/li>\n<li><a href=\"#two\">Alkylations of Acetylides With Primary Alkyl Halides: Finally, Some Carbon-Carbon Bond Formation!<\/a><\/li>\n<li><a href=\"#three\">Alkylation of Acetylides &#8211; Some Practice Questions<\/a><\/li>\n<li><a href=\"#four\">Synthesis of Substituted Acetylenes &#8211; Practice Questions<\/a><\/li>\n<li><a href=\"#five\">Other Reactions of Acetylides &#8211; Epoxide Opening and Addition to Aldehydes\/Ketones<\/a><\/li>\n<li><a href=\"#six\">Summary<\/a><\/li>\n<li><a href=\"#notes\">Notes<\/a><\/li>\n<li><a href=\"#quizzes\">Quiz Yourself!<\/a><\/li>\n<li><a href=\"#references\">(Advanced) References and Further Reading<\/a><\/li>\n<\/ol>\n<\/li>\n<\/ol>\n<hr \/>\n<h2><a id=\"one\"><\/a>1. Terminal Alkynes Are Acidic!<\/h2>\n<p>Among hydrocarbons, terminal alkynes have a very special property.\u00a0 Their C-H bonds are<strong> unusually acidic<\/strong> (pK<sub>a<\/sub> 25).<\/p>\n<p>The alkyne C-H bond is sp-hybridized. When C-H is deprotonated, the resulting carbanion is held in an orbital with 50% s-character. Since <em>s<\/em>-orbitals are closer to the nucleus than <em>p<\/em>-orbitals,\u00a0 this means that the electrons experience greater stabilization from the positively charged nucleus than the conjugate bases of alkenes and alkanes.<\/p>\n<p>Any factor which stabilizes a lone pair of electrons tends to reduce its <strong>basicity<\/strong>. (<span style=\"color: #993366;\"><em>See article &#8211;<a style=\"color: #993366;\" href=\"https:\/\/www.masterorganicchemistry.com\/2010\/09\/22\/five-key-factors-that-influence-acidity\/\"> Key Factors That Influence Acidity<\/a><\/em><\/span>). <span style=\"color: #000000;\">In fact,\u00a0 just thinking of &#8220;basicity&#8221; as a synonym for &#8220;lone-pair instability&#8221; can get you pretty far in organic chemistry!\u00a0<\/span><\/p>\n<p>A common choice of base for deprotonating the C-H bond of acetylenes is sodium amide (NaNH<sub>2<\/sub>), often used in its conjugate base, liquid ammonia (NH<sub>3<\/sub>). NaNH<sub>2<\/sub> can also be used to deprotonate the great-granddaddy of all alkynes, acetylene itself. \u00a0 [<a href=\"#noteone\"><span style=\"color: #ff0000;\">Note 1<\/span><\/a>]<\/p>\n<p><span style=\"color: #993366;\"><em>Note &#8211; don&#8217;t confuse NaNH<sub>2<\/sub>\/NH<sub>3<\/sub>\u00a0 [strong base!]\u00a0 with sodium in ammonia,Na\/NH<sub>3<\/sub>\u00a0 [reducing agent for triple bonds!]\u00a0\u00a0<\/em><span style=\"color: #000000;\">[<span style=\"color: #ff0000;\">Note 2<\/span>]<\/span><\/span><\/p>\n<p><img decoding=\"async\" class=\"alignnone wp-image-35930\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2024\/01\/1-deprotonation-of-a-terminal-alkyne-by-nanh2-to-give-terminal-acetylide.gif\" alt=\"deprotonation of a terminal alkyne by nanh2 to give terminal acetylide\" width=\"640\" height=\"321\" \/><\/a><\/p>\n<p>Acid-base reactions spontaneously proceed in the direction that gives <strong>weaker acids\u00a0<\/strong>from\u00a0<strong>stronger acids<\/strong>. (<span style=\"color: #993366;\"><em>I lovingly call this the &#8220;Principle Of Acid-Base Mediocrity&#8221; &#8211; See <span style=\"color: #993366;\">article: <a style=\"color: #993366;\" href=\"https:\/\/www.masterorganicchemistry.com\/2010\/09\/29\/how-to-use-a-pka-table\">How To Use a pKa Table<\/a><\/span><\/em><\/span>).<\/p>\n<p>Since we are proceeding from a <strong>stronger acid<\/strong> (terminal alkyne, pK<sub>a<\/sub> 25) towards a\u00a0<strong>weaker conjugate acid<\/strong> (NH<sub>3<\/sub>, pK<sub>a<\/sub> 38) the acid-base equilibrium here will be <strong>favorable<\/strong>.<\/p>\n<p>On the other hand, the acid-base reaction between NaNH<sub>2<\/sub> and alkenes (pK<sub>a<\/sub> 42) or alkanes (pK<sub>a<\/sub> 50) is <strong>unfavorable<\/strong> since it would result in a stronger acid (NH<sub>3<\/sub>, pK<sub>a<\/sub> 38), as well as a stronger base.<span style=\"color: #993366;\"><em> Remember &#8211; the stronger the acid, the weaker the conjugate base!\u00a0<\/em><\/span><\/p>\n<h2><a id=\"two\"><\/a>2. S<sub>N<\/sub>2 Reactions of Acetylides With Alkyl Halides: Finally, Some Carbon-Carbon Bond Formation!<\/h2>\n<p>OK. So we can make acetylides. Now what?<\/p>\n<p>Well, acetylides are excellent\u00a0<strong>nucleophiles<\/strong>.\u00a0 They react with alkyl halides to give internal alkynes, in a reaction known as\u00a0<strong>nucleophilic\u00a0<\/strong><em><span style=\"color: #999999;\">(aliphatic)<\/span> <\/em><strong>substitution<\/strong>.<\/p>\n<p>It is a\u00a0<strong>substitution\u00a0<\/strong>reaction because a new bond is formed (C-C) at the <strong>same<\/strong> carbon where a bond is broken (C-X, where X is a good leaving group). (<span style=\"color: #993366;\"><em>\u00a0See article: <a style=\"color: #993366;\" href=\"https:\/\/www.masterorganicchemistry.com\/2011\/04\/12\/what-makes-a-good-leaving-group\/\">What Makes a Good Leaving Group?<\/a><\/em><\/span>).<\/p>\n<p>More specifically, the substitution proceeds through an S<sub>N<\/sub>2 mechanism (<em>substitution, nucleophilic, bimolecular rate-determining step<\/em>) since the C\u2013C bond is being formed at the same time that the C\u2013X bond breaks. The reaction occurs via donation of the nucleophile lone pair into the sigma* orbital of the C-X bond, often referred to as a &#8220;backside attack&#8221;. It results in inversion of configuration at the carbon, although inversion can only be observed with carbons bearing a chiral center. (<span style=\"color: #993366;\"><em>See article: <span style=\"color: #993366;\"><a style=\"color: #993366;\" href=\"https:\/\/www.masterorganicchemistry.com\/2012\/07\/04\/the-sn2-mechanism\/\">The S<sub>N<\/sub>2 Mechanism<\/a><\/span><\/em><\/span>)<\/p>\n<p>The reaction works best for <strong>primary<\/strong> (and methyl) alkyl halides due to their lack of steric hindrance.<\/p>\n<p><img decoding=\"async\" class=\"alignnone wp-image-35931\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2024\/01\/2-terminal-acetylides-react-with-primary-alkyl-halides-to-give-internal-alkynes.gif\" alt=\"terminal acetylides react with primary alkyl halides to give internal alkynes\" width=\"640\" height=\"420\" \/><\/a><\/p>\n<p>Secondary alkyl halides tend to give elimination (E2) instead of substitution, since there is more steric hindrance at a secondary carbon and acetylide is still a very strong base &#8211; even if it&#8217;s a weak base for a hydrocarbon!<\/p>\n<p>All right. Perhaps you&#8217;ve already covered nucleophilic substitution reactions, and this reaction might not seem like such a big deal to you.\u00a0Fair.<\/p>\n<p>I would like to draw your attention, however, to the <strong>key bond\u00a0<\/strong>that is\u00a0<strong>formed<\/strong> in this reaction: <strong>C\u2013C<\/strong>.<\/p>\n<p>Up until this point, it&#8217;s unlikely you&#8217;ve covered any carbon-carbon bond forming reactions. If you&#8217;ve covered any at all, it might be the cyanide ion (e.g. NaCN) with alkyl halides. That isn&#8217;t so important for our purposes since we don&#8217;t cover reactions of cyano groups until later on in Org 2.<\/p>\n<p>Since organic chemistry is ultimately the chemistry of carbon, having the ability to form a new C-C bond from a terminal alkyne via an S<sub>N<\/sub>2 reaction is <strong>huge<\/strong> because it allows us to plan the synthesis of essentially any linear hydrocarbon from acetylene, provided we can partner it with primary alkyl halide.<\/p>\n<p><span style=\"color: #993366;\"><em>(Those primary alkyl halides can themselves be made from various reactions with acetylene, a point we&#8217;ll get to later in this chapter!).\u00a0<\/em><\/span><\/p>\n<p>The example below, for instance, shows the synthesis of 5-decyne:<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-35932\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2024\/01\/3-specific-examples-of-internal-alkyne-formation-from-terminal-alkynes-and-acetylide.gif\" alt=\"specific examples of internal alkyne formation from terminal alkynes and acetylide\" width=\"640\" height=\"407\" \/><\/a><\/p>\n<p>This reaction is extremely versatile.\u00a0Simply by changing the identity of the alkyl halide, we can\u00a0 tack on pretty much any alkyl group we want &#8211;\u00a0 so long as it&#8217;s primary &#8211; which gives us access to a huge variety of linear hydrocarbons!<\/p>\n<h2><a id=\"three\"><\/a>3. Alkylation of Acetylides &#8211; Some Practice Questions<\/h2>\n<p>We&#8217;ll get to some synthesis applications a little further below. In the meantime, see if you can draw the product of this reaction:<\/p>\n<div class=\"wq-quiz-wrapper\" data-id=\"35923\"><style type=\"text\/css\" id=\"wq-flip-custom-css\">.wq-quiz-wrapper[data-id=\"35923\"] {\n--wq-question-width: 100%;\n--wq-question-color: #009cff;\n--wq-question-height: auto;\n--wq-font-color: #444;\n}\n\n\t\t\t.wq-quiz-wrapper[data-id=\"35923\"] {\n\t\t\t\t--wq-question-width: 600px;\n\t\t\t}\n\n\t\t\t@media screen and (max-width: 600px) {\n\t\t\t\t.wq-quiz-wrapper[data-id=\"35923\"] .wq_singleQuestionWrapper { width:100% !important; height:auto !important; }\n\t\t\t}\n\t\t<\/style><!-- wp quiz -->\n<div id=\"wp-quiz-35923\" class=\"wq_quizCtr single flip_quiz wq-quiz wq-quiz-35923 wq-quiz-flip wq-layout-single wq-skin-traditional wq-should-show-correct-answer\" data-quiz-id=\"35923\">\n<div class=\"wq-questions wq_questionsCtr\">\n\t<div class=\"wq-question wq_singleQuestionWrapper wq-question-itu4s\" data-id=\"itu4s\">\n\n\t\n\t<div class=\"item_top\">\n\t\t<div class=\"title_container\">\n\t\t\t<div class=\"wq_questionTextCtr\">\n\t\t\t\t<h4 class=\"wq-question-title\"><\/h4>\n\t\t\t<\/div>\n\t\t<\/div>\n\t<\/div>\n\n\t<div class=\"card \">\n\t\t<div class=\"front\" >\n\t\n\t\t\t\t\t<img decoding=\"async\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-images\/2655-Front.gif\" \/>\n\t\t\n\t\t\n\t\n\t\n\t\t\t<span class=\"top-desc\">Click to Flip<\/span>\n\t<\/div>\n\t\t<div class=\"back\" >\n\t\n\t\t\t\t\t<img decoding=\"async\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-images\/2655-Reverse.gif\" \/>\n\t\t\n\t\t\n\t\n\t<\/div>\n\t<\/div>\n\n\t\n<\/div>\n<\/div>\n<\/div>\n<!-- \/\/ wp quiz-->\n<\/div><!-- End .wq-quiz-wrapper -->\n<p>Here is another example of a reaction between an acetylide and an alkyl halide. Can you draw the product? (D is deuterium, the heavy isotope of hydrogen).<\/p>\n<div class=\"wq-quiz-wrapper\" data-id=\"35924\"><style type=\"text\/css\" id=\"wq-flip-custom-css\">.wq-quiz-wrapper[data-id=\"35924\"] {\n--wq-question-width: 100%;\n--wq-question-color: #009cff;\n--wq-question-height: auto;\n--wq-font-color: #444;\n}\n\n\t\t\t.wq-quiz-wrapper[data-id=\"35924\"] {\n\t\t\t\t--wq-question-width: 600px;\n\t\t\t}\n\n\t\t\t@media screen and (max-width: 600px) {\n\t\t\t\t.wq-quiz-wrapper[data-id=\"35924\"] .wq_singleQuestionWrapper { width:100% !important; height:auto !important; }\n\t\t\t}\n\t\t<\/style><!-- wp quiz -->\n<div id=\"wp-quiz-35924\" class=\"wq_quizCtr single flip_quiz wq-quiz wq-quiz-35924 wq-quiz-flip wq-layout-single wq-skin-traditional wq-should-show-correct-answer\" data-quiz-id=\"35924\">\n<div class=\"wq-questions wq_questionsCtr\">\n\t<div class=\"wq-question wq_singleQuestionWrapper wq-question-5ntek\" data-id=\"5ntek\">\n\n\t\n\t<div class=\"item_top\">\n\t\t<div class=\"title_container\">\n\t\t\t<div class=\"wq_questionTextCtr\">\n\t\t\t\t<h4 class=\"wq-question-title\"><\/h4>\n\t\t\t<\/div>\n\t\t<\/div>\n\t<\/div>\n\n\t<div class=\"card \">\n\t\t<div class=\"front\" >\n\t\n\t\t\t\t\t<img decoding=\"async\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-images\/2656-Front.gif\" \/>\n\t\t\n\t\t\n\t\n\t\n\t\t\t<span class=\"top-desc\">Click to Flip<\/span>\n\t<\/div>\n\t\t<div class=\"back\" >\n\t\n\t\t\t\t\t<img decoding=\"async\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-images\/2656-Reverse.gif\" \/>\n\t\t\n\t\t\n\t\n\t<\/div>\n\t<\/div>\n\n\t\n<\/div>\n<\/div>\n<\/div>\n<!-- \/\/ wp quiz-->\n<\/div><!-- End .wq-quiz-wrapper -->\n<p>Draw the product of the reaction below:<\/p>\n<div class=\"wq-quiz-wrapper\" data-id=\"35925\"><style type=\"text\/css\" id=\"wq-flip-custom-css\">.wq-quiz-wrapper[data-id=\"35925\"] {\n--wq-question-width: 100%;\n--wq-question-color: #009cff;\n--wq-question-height: auto;\n--wq-font-color: #444;\n}\n\n\t\t\t.wq-quiz-wrapper[data-id=\"35925\"] {\n\t\t\t\t--wq-question-width: 600px;\n\t\t\t}\n\n\t\t\t@media screen and (max-width: 600px) {\n\t\t\t\t.wq-quiz-wrapper[data-id=\"35925\"] .wq_singleQuestionWrapper { width:100% !important; height:auto !important; }\n\t\t\t}\n\t\t<\/style><!-- wp quiz -->\n<div id=\"wp-quiz-35925\" class=\"wq_quizCtr single flip_quiz wq-quiz wq-quiz-35925 wq-quiz-flip wq-layout-single wq-skin-traditional wq-should-show-correct-answer\" data-quiz-id=\"35925\">\n<div class=\"wq-questions wq_questionsCtr\">\n\t<div class=\"wq-question wq_singleQuestionWrapper wq-question-d2fr0\" data-id=\"d2fr0\">\n\n\t\n\t<div class=\"item_top\">\n\t\t<div class=\"title_container\">\n\t\t\t<div class=\"wq_questionTextCtr\">\n\t\t\t\t<h4 class=\"wq-question-title\"><\/h4>\n\t\t\t<\/div>\n\t\t<\/div>\n\t<\/div>\n\n\t<div class=\"card \">\n\t\t<div class=\"front\" >\n\t\n\t\t\t\t\t<img decoding=\"async\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-images\/2657-Front.gif\" \/>\n\t\t\n\t\t\n\t\n\t\n\t\t\t<span class=\"top-desc\">Click to Flip<\/span>\n\t<\/div>\n\t\t<div class=\"back\" >\n\t\n\t\t\t\t\t<img decoding=\"async\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-images\/2657-Reverse.gif\" \/>\n\t\t\n\t\t\n\t\n\t<\/div>\n\t<\/div>\n\n\t\n<\/div>\n<\/div>\n<\/div>\n<!-- \/\/ wp quiz-->\n<\/div><!-- End .wq-quiz-wrapper -->\n<p>In the reaction below, the acetylide is treated with an alkyl halide containing\u00a0<em>two<\/em> leaving groups. Draw the product!<\/p>\n<div class=\"wq-quiz-wrapper\" data-id=\"35926\"><style type=\"text\/css\" id=\"wq-flip-custom-css\">.wq-quiz-wrapper[data-id=\"35926\"] {\n--wq-question-width: 100%;\n--wq-question-color: #009cff;\n--wq-question-height: auto;\n--wq-font-color: #444;\n}\n\n\t\t\t.wq-quiz-wrapper[data-id=\"35926\"] {\n\t\t\t\t--wq-question-width: 600px;\n\t\t\t}\n\n\t\t\t@media screen and (max-width: 600px) {\n\t\t\t\t.wq-quiz-wrapper[data-id=\"35926\"] .wq_singleQuestionWrapper { width:100% !important; height:auto !important; }\n\t\t\t}\n\t\t<\/style><!-- wp quiz -->\n<div id=\"wp-quiz-35926\" class=\"wq_quizCtr single flip_quiz wq-quiz wq-quiz-35926 wq-quiz-flip wq-layout-single wq-skin-traditional wq-should-show-correct-answer\" data-quiz-id=\"35926\">\n<div class=\"wq-questions wq_questionsCtr\">\n\t<div class=\"wq-question wq_singleQuestionWrapper wq-question-pabf4\" data-id=\"pabf4\">\n\n\t\n\t<div class=\"item_top\">\n\t\t<div class=\"title_container\">\n\t\t\t<div class=\"wq_questionTextCtr\">\n\t\t\t\t<h4 class=\"wq-question-title\"><\/h4>\n\t\t\t<\/div>\n\t\t<\/div>\n\t<\/div>\n\n\t<div class=\"card \">\n\t\t<div class=\"front\" >\n\t\n\t\t\t\t\t<img decoding=\"async\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-images\/2658-Front.gif\" \/>\n\t\t\n\t\t\n\t\n\t\n\t\t\t<span class=\"top-desc\">Click to Flip<\/span>\n\t<\/div>\n\t\t<div class=\"back\" >\n\t\n\t\t\t\t\t<img decoding=\"async\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-images\/2658-Reverse.gif\" \/>\n\t\t\n\t\t\n\t\n\t<\/div>\n\t<\/div>\n\n\t\n<\/div>\n<\/div>\n<\/div>\n<!-- \/\/ wp quiz-->\n<\/div><!-- End .wq-quiz-wrapper -->\n<h2><a id=\"four\"><\/a>4. Practice Questions &#8211; Synthesis of Acetylenes<\/h2>\n<p>As mentioned above in section two, the S<sub>N<\/sub>2 reaction between acetylides and alkyl halides means that we can build up pretty much\u00a0any linear alkyne from acetylene, provided that we have the necessary (linear) alkyl halides.<\/p>\n<p>The questions below ask you to show how you would synthesize internal alkynes from acetylene and alkyl halides.<\/p>\n<p>Here&#8217;s one synthesis problem:<\/p>\n<div class=\"wq-quiz-wrapper\" data-id=\"35927\"><style type=\"text\/css\" id=\"wq-flip-custom-css\">.wq-quiz-wrapper[data-id=\"35927\"] {\n--wq-question-width: 100%;\n--wq-question-color: #009cff;\n--wq-question-height: auto;\n--wq-font-color: #444;\n}\n\n\t\t\t.wq-quiz-wrapper[data-id=\"35927\"] {\n\t\t\t\t--wq-question-width: 600px;\n\t\t\t}\n\n\t\t\t@media screen and (max-width: 600px) {\n\t\t\t\t.wq-quiz-wrapper[data-id=\"35927\"] .wq_singleQuestionWrapper { width:100% !important; height:auto !important; }\n\t\t\t}\n\t\t<\/style><!-- wp quiz -->\n<div id=\"wp-quiz-35927\" class=\"wq_quizCtr single flip_quiz wq-quiz wq-quiz-35927 wq-quiz-flip wq-layout-single wq-skin-traditional wq-should-show-correct-answer\" data-quiz-id=\"35927\">\n<div class=\"wq-questions wq_questionsCtr\">\n\t<div class=\"wq-question wq_singleQuestionWrapper wq-question-sz734\" data-id=\"sz734\">\n\n\t\n\t<div class=\"item_top\">\n\t\t<div class=\"title_container\">\n\t\t\t<div class=\"wq_questionTextCtr\">\n\t\t\t\t<h4 class=\"wq-question-title\"><\/h4>\n\t\t\t<\/div>\n\t\t<\/div>\n\t<\/div>\n\n\t<div class=\"card \">\n\t\t<div class=\"front\" >\n\t\n\t\t\t\t\t<img decoding=\"async\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-images\/2659-Front.gif\" \/>\n\t\t\n\t\t\n\t\n\t\n\t\t\t<span class=\"top-desc\">Click to Flip<\/span>\n\t<\/div>\n\t\t<div class=\"back\" >\n\t\n\t\t\t\t\t<img decoding=\"async\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-images\/2659-Reverse.gif\" \/>\n\t\t\n\t\t\n\t\n\t<\/div>\n\t<\/div>\n\n\t\n<\/div>\n<\/div>\n<\/div>\n<!-- \/\/ wp quiz-->\n<\/div><!-- End .wq-quiz-wrapper -->\n<p>A second, slightly more difficult synthesis question.<\/p>\n<div class=\"wq-quiz-wrapper\" data-id=\"35928\"><style type=\"text\/css\" id=\"wq-flip-custom-css\">.wq-quiz-wrapper[data-id=\"35928\"] {\n--wq-question-width: 100%;\n--wq-question-color: #009cff;\n--wq-question-height: auto;\n--wq-font-color: #444;\n}\n\n\t\t\t.wq-quiz-wrapper[data-id=\"35928\"] {\n\t\t\t\t--wq-question-width: 600px;\n\t\t\t}\n\n\t\t\t@media screen and (max-width: 600px) {\n\t\t\t\t.wq-quiz-wrapper[data-id=\"35928\"] .wq_singleQuestionWrapper { width:100% !important; height:auto !important; }\n\t\t\t}\n\t\t<\/style><!-- wp quiz -->\n<div id=\"wp-quiz-35928\" class=\"wq_quizCtr single flip_quiz wq-quiz wq-quiz-35928 wq-quiz-flip wq-layout-single wq-skin-traditional wq-should-show-correct-answer\" data-quiz-id=\"35928\">\n<div class=\"wq-questions wq_questionsCtr\">\n\t<div class=\"wq-question wq_singleQuestionWrapper wq-question-ppcen\" data-id=\"ppcen\">\n\n\t\n\t<div class=\"item_top\">\n\t\t<div class=\"title_container\">\n\t\t\t<div class=\"wq_questionTextCtr\">\n\t\t\t\t<h4 class=\"wq-question-title\"><\/h4>\n\t\t\t<\/div>\n\t\t<\/div>\n\t<\/div>\n\n\t<div class=\"card \">\n\t\t<div class=\"front\" >\n\t\n\t\t\t\t\t<img decoding=\"async\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-images\/2660-Front.gif\" \/>\n\t\t\n\t\t\n\t\n\t\n\t\t\t<span class=\"top-desc\">Click to Flip<\/span>\n\t<\/div>\n\t\t<div class=\"back\" >\n\t\n\t\t\t\t\t<img decoding=\"async\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-images\/2660-Reverse.gif\" \/>\n\t\t\n\t\t\n\t\n\t<\/div>\n\t<\/div>\n\n\t\n<\/div>\n<\/div>\n<\/div>\n<!-- \/\/ wp quiz-->\n<\/div><!-- End .wq-quiz-wrapper -->\n<p>More of the same thing!<\/p>\n<div class=\"wq-quiz-wrapper\" data-id=\"35929\"><style type=\"text\/css\" id=\"wq-flip-custom-css\">.wq-quiz-wrapper[data-id=\"35929\"] {\n--wq-question-width: 100%;\n--wq-question-color: #009cff;\n--wq-question-height: auto;\n--wq-font-color: #444;\n}\n\n\t\t\t.wq-quiz-wrapper[data-id=\"35929\"] {\n\t\t\t\t--wq-question-width: 600px;\n\t\t\t}\n\n\t\t\t@media screen and (max-width: 600px) {\n\t\t\t\t.wq-quiz-wrapper[data-id=\"35929\"] .wq_singleQuestionWrapper { width:100% !important; height:auto !important; }\n\t\t\t}\n\t\t<\/style><!-- wp quiz -->\n<div id=\"wp-quiz-35929\" class=\"wq_quizCtr single flip_quiz wq-quiz wq-quiz-35929 wq-quiz-flip wq-layout-single wq-skin-traditional wq-should-show-correct-answer\" data-quiz-id=\"35929\">\n<div class=\"wq-questions wq_questionsCtr\">\n\t<div class=\"wq-question wq_singleQuestionWrapper wq-question-e4mt5\" data-id=\"e4mt5\">\n\n\t\n\t<div class=\"item_top\">\n\t\t<div class=\"title_container\">\n\t\t\t<div class=\"wq_questionTextCtr\">\n\t\t\t\t<h4 class=\"wq-question-title\"><\/h4>\n\t\t\t<\/div>\n\t\t<\/div>\n\t<\/div>\n\n\t<div class=\"card \">\n\t\t<div class=\"front\" >\n\t\n\t\t\t\t\t<img decoding=\"async\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-images\/2661-Front.gif\" \/>\n\t\t\n\t\t\n\t\n\t\n\t\t\t<span class=\"top-desc\">Click to Flip<\/span>\n\t<\/div>\n\t\t<div class=\"back\" >\n\t\n\t\t\t\t\t<img decoding=\"async\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-images\/2661-Reverse.gif\" \/>\n\t\t\n\t\t\n\t\n\t<\/div>\n\t<\/div>\n\n\t\n<\/div>\n<\/div>\n<\/div>\n<!-- \/\/ wp quiz-->\n<\/div><!-- End .wq-quiz-wrapper -->\n<h2><a id=\"five\"><\/a>5. Reaction of Acetylides With Other Nucleophiles<\/h2>\n<p>Acetylides don&#8217;t just react with alkyl halides! They are versatile nucleophiles with other electrophiles as well, although you might not see some of these reactions until later in your course, or perhaps in the second semester of a two-semester course.<\/p>\n<p><strong>Epoxides<\/strong> are 3-membered cyclic ethers with considerable ring strain (about 13 kcal\/mol) (<span style=\"color: #993366;\"><em>See article &#8211; <span style=\"color: #993366;\"><a style=\"color: #993366;\" href=\"https:\/\/www.masterorganicchemistry.com\/2015\/01\/26\/epoxides-the-outlier-of-the-ether-family\/\">Epoxides, The Outlier of the Ether Family<\/a><\/span><\/em><\/span>).\u00a0 Acetylides will react with epoxides at the <strong>least<\/strong> substituted position to form new C-C bonds (<span style=\"color: #993366;\"><em>See Article: <a style=\"color: #993366;\" href=\"https:\/\/www.masterorganicchemistry.com\/2015\/02\/10\/opening-of-epoxide-with-base\/\">Epoxide Ring-Opening With Base<\/a><\/em><\/span>)<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-35933\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2024\/01\/11-other-reactions-of-acetylides-include-addition-of-acetylide-ions-to-least-substituted-carbon-of-epoxides.gif\" alt=\"other reactions of acetylides include addition of acetylide ions to least substituted carbon of epoxides\" width=\"640\" height=\"282\" \/><\/a><\/p>\n<p>Acetylides will also add to aldehydes and ketones through nucleophilic addition to the C-O pi bond. In this respect the reaction of acetylides is essentially identical to those of Grignard reagents.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-35935\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2024\/01\/12-addition-of-acetylide-ions-to-aldehydes-and-ketones-results-in-alchols-1.gif\" alt=\"addition of acetylide ions to aldehydes and ketones results in alchols\" width=\"640\" height=\"269\" \/><\/a><\/p>\n<h2><a id=\"six\"><\/a>6. Summary<\/h2>\n<ul>\n<li>Acetylides react with primary and methyl alkyl halides to give new C-C bonds via nucleophilic substitution (S<sub>N<\/sub>2 mechanism).<\/li>\n<li>They tend to give elimination with secondary alkyl halides.<\/li>\n<li>This is an extremely important reaction for first semester organic chemistry, as it allows for formation of longer carbon chains from acetylene.<\/li>\n<\/ul>\n<p>In the next article in this series, we will show how the triple bond of alkynes can be partially hydrogenated to give alkenes. (<span style=\"color: #993366;\"><em>See article: <span style=\"color: #993366;\"><a style=\"color: #993366;\" href=\"https:\/\/www.masterorganicchemistry.com\/2011\/08\/19\/lindlars-catalyst-partial-cis-reduction\/\">Partial Hydrogenation of Alkynes to Give Alkenes<\/a><\/span><\/em><\/span>)<\/p>\n<hr \/>\n<h2><strong><a id=\"notes\"><\/a>Notes<\/strong><\/h2>\n<div class=\"related-articles\"><p><strong>Related Articles<\/strong><\/p><ul><li><a href=\"https:\/\/www.masterorganicchemistry.com\/2011\/08\/19\/lindlars-catalyst-partial-cis-reduction\/\" class=\"\"><span>Partial Reduction of Alkynes With Lindlar\u2019s Catalyst<\/span><\/a><\/li><li><a href=\"https:\/\/www.masterorganicchemistry.com\/2013\/05\/08\/nanh3-partial-reduction-of-alkynes\/\" class=\"\"><span>Partial Reduction of Alkynes With Na\/NH3 To Obtain Trans Alkenes<\/span><\/a><\/li><li><a href=\"https:\/\/www.masterorganicchemistry.com\/2024\/01\/23\/alkyne-hydroboration-with-r2bh\/\" class=\"\"><span>Alkyne Hydroboration With \u201cR2BH\u201d<\/span><\/a><\/li><li><a href=\"https:\/\/www.masterorganicchemistry.com\/2010\/09\/22\/five-key-factors-that-influence-acidity\/\" class=\"\"><span>Five Key Factors That Influence Acidity<\/span><\/a><\/li><li><a href=\"https:\/\/www.masterorganicchemistry.com\/2012\/07\/04\/the-sn2-mechanism\/\" class=\"\"><span>The SN2 Mechanism<\/span><\/a><\/li><li><a href=\"https:\/\/www.masterorganicchemistry.com\/2012\/02\/27\/7-factors-that-stabilize-negative-charge-in-organic-chemistry\/\" class=\"\"><span>7 Factors that stabilize negative charge in organic chemistry<\/span><\/a><\/li><li><a href=\"https:\/\/www.masterorganicchemistry.com\/2017\/10\/10\/hybrid-orbitals\/\" class=\"\"><span>Hybrid Orbitals and Hybridization<\/span><\/a><\/li><li><a href=\"https:\/\/www.masterorganicchemistry.com\/2012\/07\/11\/why-the-sn2-reaction-is-powerful\/\" class=\"\"><span>Why the SN2 Reaction Is Powerful<\/span><\/a><\/li><li><a href=\"https:\/\/www.masterorganicchemistry.com\/2012\/06\/18\/what-makes-a-good-nucleophile\/\" class=\"\"><span>What Makes A Good Nucleophile?<\/span><\/a><\/li><li><a href=\"https:\/\/www.masterorganicchemistry.com\/2013\/06\/24\/alkynes-are-a-blank-canvas\/\" class=\"\"><span>Alkynes Are A Blank Canvas<\/span><\/a><\/li><\/ul><\/div>\n<p><strong>Note 1.\u00a0<\/strong>Conditions for the deprotonation of acetylene are <a href=\"http:\/\/orgsyn.org\/demo.aspx?prep=cv4p0117\">here<\/a>. Note that acetylene is a gas, so it has to be bubbled through a solution containing NaNH<sub>2<\/sub> in ammonia. These days, it&#8217;s more common just to just purchase the conjugate base of acetylene (<span style=\"color: #993366;\"><em>such as lithium acetylide, diethylamine complex<\/em><\/span>) directly from a commercial supplier like <a href=\"https:\/\/www.sigmaaldrich.com\/US\/en\/product\/aldrich\/186155\">Aldrich<\/a> and weigh it out.<\/p>\n<p><strong>Note 2<\/strong>. By no means is NaNH<sub>2<\/sub> the only base used for deprotonating acetylenes, it just seems to be the textbook reagent of choice. Grignard and organolithium reagents are also often used to form acetylides.<\/p>\n<hr \/>\n<h2><strong><a id=\"quizzes\"><\/a>Quiz Yourself!<\/strong><\/h2>\n<p><div class=\"wq-quiz-wrapper\" data-id=\"41280\"><style type=\"text\/css\" id=\"wq-flip-custom-css\">.wq-quiz-wrapper[data-id=\"41280\"] {\n--wq-question-width: 100%;\n--wq-question-color: #009cff;\n--wq-question-height: auto;\n--wq-font-color: #444;\n}\n\n\t\t\t.wq-quiz-wrapper[data-id=\"41280\"] {\n\t\t\t\t--wq-question-width: 600px;\n\t\t\t}\n\n\t\t\t@media screen and (max-width: 600px) {\n\t\t\t\t.wq-quiz-wrapper[data-id=\"41280\"] .wq_singleQuestionWrapper { width:100% !important; height:auto !important; }\n\t\t\t}\n\t\t<\/style><!-- wp quiz -->\n<div id=\"wp-quiz-41280\" class=\"wq_quizCtr single flip_quiz wq-quiz wq-quiz-41280 wq-quiz-flip wq-layout-single wq-skin-traditional wq-should-show-correct-answer\" data-quiz-id=\"41280\">\n<div class=\"wq-questions wq_questionsCtr\">\n\t<div class=\"wq-question wq_singleQuestionWrapper wq-question-8u10x\" data-id=\"8u10x\">\n\n\t\n\t<div class=\"item_top\">\n\t\t<div class=\"title_container\">\n\t\t\t<div class=\"wq_questionTextCtr\">\n\t\t\t\t<h4 class=\"wq-question-title\"><\/h4>\n\t\t\t<\/div>\n\t\t<\/div>\n\t<\/div>\n\n\t<div class=\"card \">\n\t\t<div class=\"front\" >\n\t\n\t\t\t\t\t<img decoding=\"async\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-images\/3334-Front.gif\" \/>\n\t\t\n\t\t\n\t\n\t\n\t\t\t<span class=\"top-desc\">Click to Flip<\/span>\n\t<\/div>\n\t\t<div class=\"back\" >\n\t\n\t\t\t\t\t<img decoding=\"async\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-images\/3334-Reverse.gif\" \/>\n\t\t\n\t\t\n\t\n\t<\/div>\n\t<\/div>\n\n\t\n<\/div>\n<\/div>\n<\/div>\n<!-- \/\/ wp quiz-->\n<\/div><!-- End .wq-quiz-wrapper --><br \/>\n<br \/>\n<img loading=\"lazy\" decoding=\"async\" class=\"wp-image-36214 aligncenter\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-previews\/0690-Front-Image-Only.png\" alt=\"\" width=\"600\" height=\"450\" \/><\/a><\/p>\n<p style=\"text-align: center;\"><a href=\"https:\/\/www.masterorganicchemistry.com\/moc-membership\/\"><strong>Become a MOC member<\/strong><\/a> to see the clickable quiz with answers on the back.<\/p>\n<p><br \/>\n<br \/>\n<img loading=\"lazy\" decoding=\"async\" class=\"wp-image-36214 aligncenter\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-previews\/0694-Front-Image-Only.png\" alt=\"\" width=\"600\" height=\"450\" \/><\/a><\/p>\n<p style=\"text-align: center;\"><a href=\"https:\/\/www.masterorganicchemistry.com\/moc-membership\/\"><strong>Become a MOC member<\/strong><\/a> to see the clickable quiz with answers on the back.<\/p>\n<p><br \/>\n<br \/>\n<img loading=\"lazy\" decoding=\"async\" class=\"wp-image-36214 aligncenter\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-previews\/0730-Front-Image-Only.png\" alt=\"\" width=\"600\" height=\"450\" \/><\/a><\/p>\n<p style=\"text-align: center;\"><a href=\"https:\/\/www.masterorganicchemistry.com\/moc-membership\/\"><strong>Become a MOC member<\/strong><\/a> to see the clickable quiz with answers on the back.<\/p>\n<p><br \/>\n<br \/>\n<img loading=\"lazy\" decoding=\"async\" class=\"wp-image-36214 aligncenter\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-previews\/0733-Front-Image-Only.png\" alt=\"\" width=\"600\" height=\"450\" \/><\/a><\/p>\n<p style=\"text-align: center;\"><a href=\"https:\/\/www.masterorganicchemistry.com\/moc-membership\/\"><strong>Become a MOC member<\/strong><\/a> to see the clickable quiz with answers on the back.<\/p>\n<p><br \/>\n<br \/>\n<img loading=\"lazy\" decoding=\"async\" class=\"wp-image-36214 aligncenter\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-previews\/1649-Front-Image-Only.png\" alt=\"\" width=\"600\" height=\"450\" \/><\/a><\/p>\n<p style=\"text-align: center;\"><a href=\"https:\/\/www.masterorganicchemistry.com\/moc-membership\/\"><strong>Become a MOC member<\/strong><\/a> to see the clickable quiz with answers on the back.<\/p>\n<p><br \/>\n<br \/>\n<img loading=\"lazy\" decoding=\"async\" class=\"wp-image-36214 aligncenter\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-previews\/1650-Front-Image-Only.png\" alt=\"\" width=\"600\" height=\"450\" \/><\/a><\/p>\n<p style=\"text-align: center;\"><a href=\"https:\/\/www.masterorganicchemistry.com\/moc-membership\/\"><strong>Become a MOC member<\/strong><\/a> to see the clickable quiz with answers on the back.<\/p>\n<p><br \/>\n<br \/>\n<img loading=\"lazy\" decoding=\"async\" class=\"wp-image-36214 aligncenter\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-previews\/1651-Front-Image-Only.png\" alt=\"\" width=\"600\" height=\"450\" \/><\/a><\/p>\n<p style=\"text-align: center;\"><a href=\"https:\/\/www.masterorganicchemistry.com\/moc-membership\/\"><strong>Become a MOC member<\/strong><\/a> to see the clickable quiz with answers on the back.<\/p>\n<p><br \/>\n<br \/>\n<img loading=\"lazy\" decoding=\"async\" class=\"wp-image-36214 aligncenter\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-previews\/2086-Front-Image-Only.png\" alt=\"\" width=\"600\" height=\"450\" \/><\/a><\/p>\n<p style=\"text-align: center;\"><a href=\"https:\/\/www.masterorganicchemistry.com\/moc-membership\/\"><strong>Become a MOC member<\/strong><\/a> to see the clickable quiz with answers on the back.<\/p>\n<p><\/p>\n<hr \/>\n<h2><strong><a id=\"references\"><\/a>(Advanced) References and Further Reading<\/strong><\/h2>\n<p>This is a pretty standard acid-base reaction, driven by the acidity of the <em>sp<\/em>-H atom. The utility lies in that this is still a robust method of C-C bond formation, and a useful way to introduce alkynyl groups if desired.<\/p>\n<ol>\n<li><strong>THE PREPARATION AND ALKYLATION OF METAL ACETYLIDES IN LIQUID AMMONIA*<\/strong><br \/>\nT. H. Vaughn, G. F. Hennion, R. R. Vogt, and J. A. Nieuwland<br \/>\n<em>The Journal of Organic Chemistry<\/em> <strong>1937<\/strong> 02 (1), 1-22<br \/>\n<strong>DOI<\/strong>: <a href=\"https:\/\/pubs.acs.org\/doi\/10.1021\/jo01224a001\">10.1021\/jo01224a001<\/a><\/li>\n<li><strong>PREPARATION AND USE OF LITHIUM ACETYLIDE: 1-METHYL-2-ETHYNYL-endo-3,3-DIMETHYL-2-NORBORNANOL<br \/>\n<\/strong> Mark Midland, Jim I. McLoughlin, and Ralph T. Werley Jr<br \/>\n<em>Org. Synth. <\/em><strong>1990<\/strong><em>, 68, <\/em>14<em><br \/>\n<\/em><strong>DOI<\/strong>: <a href=\"http:\/\/www.orgsyn.org\/demo.aspx?prep=CV8P0391\">10.15227\/orgsyn.068.0014<\/a><br \/>\nI was initially a little surprised that something like this was published so recently in Organic Syntheses, but reading the discussion gives some context. The selective formation of the <em>monolithiated<\/em> species from deprotonation of acetylene is tricky.<\/li>\n<li><strong>1-PHENYL-1-PENTEN-4-YN-3-OL<\/strong><br \/>\nLars Skatteb\u00f8l, E. R. H. Jones, and Mark C. Whiting<br \/>\n<em>Org. Synth.<\/em> <strong>1959<\/strong>, <em>39<\/em>, 56<br \/>\n<strong>DOI<\/strong>: <a href=\"http:\/\/www.orgsyn.org\/demo.aspx?prep=CV4P0792\">10.15227\/orgsyn.039.0056<\/a><br \/>\nAlkynyl Grignards can also be formed by deprotonation of a terminal alkyne with a Grignard reagent, as this procedure demonstrates.<\/li>\n<li><strong>n-BUTYLACETYLENE<br \/>\n<\/strong>Kenneth N. Campbell and Barbara K. Campbell<br \/>\n<em>Org. Synth. <\/em><strong>1950<\/strong> <em>30<\/em>, 15<br \/>\n<strong>DOI<\/strong>: <a href=\"http:\/\/orgsyn.org\/demo.aspx?prep=cv4p0117\">10.15227\/orgsyn.030.0015<\/a><br \/>\nAn extremely simple example of this reaction. The deprotonation is done with Na metal in liquid ammonia, and care has to be taken to avoid the conditions of dissolving metal reduction (the procedure states that the reaction should not turn blue)<\/li>\n<li><strong>Synthesis of Unsymmetrical Alkynes via the Alkylation of Sodium Acetylides. An Introduction to Synthetic Design for Organic Chemistry Students<br \/>\n<\/strong>Jennifer N. Shepherd and Jason R. Stenzel<br \/>\n<em>Journal of Chemical Education<\/em><strong> 2006, <\/strong><em>83<\/em> (3), 425<br \/>\n<strong>DOI: <\/strong><a href=\"https:\/\/pubs.acs.org\/doi\/10.1021\/ed083p425\">10.1021\/ed083p425<\/a><br \/>\nA nice paper that describes the adaptation of this reaction for undergraduate teaching labs.<\/li>\n<\/ol>\n","protected":false},"excerpt":{"rendered":"<p>Alkylation of acetylides Terminal alkynes have unusually acidic C\u2013H bonds (pKa 25). Treatment with a strong base such as sodium amide (NaNH2) gives an acetylide, <\/p>\n","protected":false},"author":1,"featured_media":35941,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[1419],"tags":[163,477,271,615,279,352],"post_folder":[],"class_list":["post-7256","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-alkyne-reactions","tag-acidity","tag-alkynes-2","tag-sn2","tag-sp","tag-substitution","tag-synthesis"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.7 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Acetylides from Alkynes, and The Substitution Reactions of Acetylides<\/title>\n<meta name=\"description\" content=\"What are the two most important reactions of alkynes? First, deprotonation to give an acetylide. Then, SN2 of the acetylide with an alkyl halide forming C\u2013C\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.masterorganicchemistry.com\/2013\/05\/01\/acetylide-formation-alkylation\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Acetylides from Alkynes, and The Substitution Reactions of Acetylides\" \/>\n<meta property=\"og:description\" content=\"What are the two most important reactions of alkynes? First, deprotonation to give an acetylide. Then, SN2 of the acetylide with an alkyl halide forming C\u2013C\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.masterorganicchemistry.com\/2013\/05\/01\/acetylide-formation-alkylation\/\" \/>\n<meta property=\"og:site_name\" content=\"Master Organic Chemistry\" \/>\n<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/Master-Organic-Chemistry-242610599108055\/\" \/>\n<meta property=\"article:published_time\" content=\"2013-05-01T12:03:07+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2026-04-21T15:45:03+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2013\/05\/0-summary-alkylation-of-alkyynes-through-deprotonation-and-reaction-with-alkyl-halides.gif\" \/>\n\t<meta property=\"og:image:width\" content=\"920\" \/>\n\t<meta property=\"og:image:height\" content=\"576\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/gif\" \/>\n<meta name=\"author\" content=\"James Ashenhurst\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"James Ashenhurst\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"10 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/2013\\\/05\\\/01\\\/acetylide-formation-alkylation\\\/#article\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/2013\\\/05\\\/01\\\/acetylide-formation-alkylation\\\/\"},\"author\":{\"name\":\"James Ashenhurst\",\"@id\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/#\\\/schema\\\/person\\\/78d83ec7d02b4b7365bade2cedaef80c\"},\"headline\":\"Acetylides from Alkynes, And Substitution Reactions of Acetylides\",\"datePublished\":\"2013-05-01T12:03:07+00:00\",\"dateModified\":\"2026-04-21T15:45:03+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/2013\\\/05\\\/01\\\/acetylide-formation-alkylation\\\/\"},\"wordCount\":1997,\"commentCount\":11,\"publisher\":{\"@id\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/#organization\"},\"image\":{\"@id\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/2013\\\/05\\\/01\\\/acetylide-formation-alkylation\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/wp-content\\\/uploads\\\/2013\\\/05\\\/0-summary-alkylation-of-alkyynes-through-deprotonation-and-reaction-with-alkyl-halides.gif\",\"keywords\":[\"acidity\",\"alkynes\",\"SN2\",\"sp\",\"substitution\",\"synthesis\"],\"articleSection\":[\"Alkyne Reactions\"],\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"CommentAction\",\"name\":\"Comment\",\"target\":[\"https:\\\/\\\/www.masterorganicchemistry.com\\\/2013\\\/05\\\/01\\\/acetylide-formation-alkylation\\\/#respond\"]}]},{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/2013\\\/05\\\/01\\\/acetylide-formation-alkylation\\\/\",\"url\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/2013\\\/05\\\/01\\\/acetylide-formation-alkylation\\\/\",\"name\":\"Acetylides from Alkynes, and The Substitution Reactions of Acetylides\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/2013\\\/05\\\/01\\\/acetylide-formation-alkylation\\\/#primaryimage\"},\"image\":{\"@id\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/2013\\\/05\\\/01\\\/acetylide-formation-alkylation\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/wp-content\\\/uploads\\\/2013\\\/05\\\/0-summary-alkylation-of-alkyynes-through-deprotonation-and-reaction-with-alkyl-halides.gif\",\"datePublished\":\"2013-05-01T12:03:07+00:00\",\"dateModified\":\"2026-04-21T15:45:03+00:00\",\"description\":\"What are the two most important reactions of alkynes? First, deprotonation to give an acetylide. Then, SN2 of the acetylide with an alkyl halide forming C\u2013C\",\"breadcrumb\":{\"@id\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/2013\\\/05\\\/01\\\/acetylide-formation-alkylation\\\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\\\/\\\/www.masterorganicchemistry.com\\\/2013\\\/05\\\/01\\\/acetylide-formation-alkylation\\\/\"]}]},{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/2013\\\/05\\\/01\\\/acetylide-formation-alkylation\\\/#primaryimage\",\"url\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/wp-content\\\/uploads\\\/2013\\\/05\\\/0-summary-alkylation-of-alkyynes-through-deprotonation-and-reaction-with-alkyl-halides.gif\",\"contentUrl\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/wp-content\\\/uploads\\\/2013\\\/05\\\/0-summary-alkylation-of-alkyynes-through-deprotonation-and-reaction-with-alkyl-halides.gif\",\"width\":920,\"height\":576,\"caption\":\"summary- alkylation of alkyynes through deprotonation and reaction with alkyl halides\"},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/2013\\\/05\\\/01\\\/acetylide-formation-alkylation\\\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Acetylides from Alkynes, And Substitution Reactions of Acetylides\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/#website\",\"url\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/\",\"name\":\"Master Organic Chemistry\",\"description\":\"\",\"publisher\":{\"@id\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/#organization\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"en-US\"},{\"@type\":\"Organization\",\"@id\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/#organization\",\"name\":\"Master Organic Chemistry\",\"url\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/\",\"logo\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/#\\\/schema\\\/logo\\\/image\\\/\",\"url\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/wp-content\\\/uploads\\\/2019\\\/04\\\/cutmypic.png\",\"contentUrl\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/wp-content\\\/uploads\\\/2019\\\/04\\\/cutmypic.png\",\"width\":225,\"height\":225,\"caption\":\"Master Organic Chemistry\"},\"image\":{\"@id\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/#\\\/schema\\\/logo\\\/image\\\/\"},\"sameAs\":[\"https:\\\/\\\/www.facebook.com\\\/Master-Organic-Chemistry-242610599108055\\\/\"]},{\"@type\":\"Person\",\"@id\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/#\\\/schema\\\/person\\\/78d83ec7d02b4b7365bade2cedaef80c\",\"name\":\"James Ashenhurst\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/f9e9df435875e5e6b0bdff6b8522a7279d5717644b3efa7299da22c837bf9fcf?s=96&d=retro&r=g\",\"url\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/f9e9df435875e5e6b0bdff6b8522a7279d5717644b3efa7299da22c837bf9fcf?s=96&d=retro&r=g\",\"contentUrl\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/f9e9df435875e5e6b0bdff6b8522a7279d5717644b3efa7299da22c837bf9fcf?s=96&d=retro&r=g\",\"caption\":\"James Ashenhurst\"},\"description\":\"Ph.D. 2006, McGill University (James L. Gleason). Postdoctoral Associate, 2008-2010, Massachusetts Institute of Technology (M. Movassaghi). Founder, Master Organic Chemistry, 2010-present.\",\"sameAs\":[\"https:\\\/\\\/www.masterorganicchemistry.com\\\/about\\\/\"],\"url\":\"https:\\\/\\\/www.masterorganicchemistry.com\\\/author\\\/james\\\/\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Acetylides from Alkynes, and The Substitution Reactions of Acetylides","description":"What are the two most important reactions of alkynes? First, deprotonation to give an acetylide. Then, SN2 of the acetylide with an alkyl halide forming C\u2013C","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/www.masterorganicchemistry.com\/2013\/05\/01\/acetylide-formation-alkylation\/","og_locale":"en_US","og_type":"article","og_title":"Acetylides from Alkynes, and The Substitution Reactions of Acetylides","og_description":"What are the two most important reactions of alkynes? First, deprotonation to give an acetylide. Then, SN2 of the acetylide with an alkyl halide forming C\u2013C","og_url":"https:\/\/www.masterorganicchemistry.com\/2013\/05\/01\/acetylide-formation-alkylation\/","og_site_name":"Master Organic Chemistry","article_publisher":"https:\/\/www.facebook.com\/Master-Organic-Chemistry-242610599108055\/","article_published_time":"2013-05-01T12:03:07+00:00","article_modified_time":"2026-04-21T15:45:03+00:00","og_image":[{"width":920,"height":576,"url":"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2013\/05\/0-summary-alkylation-of-alkyynes-through-deprotonation-and-reaction-with-alkyl-halides.gif","type":"image\/gif"}],"author":"James Ashenhurst","twitter_card":"summary_large_image","twitter_misc":{"Written by":"James Ashenhurst","Est. reading time":"10 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/www.masterorganicchemistry.com\/2013\/05\/01\/acetylide-formation-alkylation\/#article","isPartOf":{"@id":"https:\/\/www.masterorganicchemistry.com\/2013\/05\/01\/acetylide-formation-alkylation\/"},"author":{"name":"James Ashenhurst","@id":"https:\/\/www.masterorganicchemistry.com\/#\/schema\/person\/78d83ec7d02b4b7365bade2cedaef80c"},"headline":"Acetylides from Alkynes, And Substitution Reactions of Acetylides","datePublished":"2013-05-01T12:03:07+00:00","dateModified":"2026-04-21T15:45:03+00:00","mainEntityOfPage":{"@id":"https:\/\/www.masterorganicchemistry.com\/2013\/05\/01\/acetylide-formation-alkylation\/"},"wordCount":1997,"commentCount":11,"publisher":{"@id":"https:\/\/www.masterorganicchemistry.com\/#organization"},"image":{"@id":"https:\/\/www.masterorganicchemistry.com\/2013\/05\/01\/acetylide-formation-alkylation\/#primaryimage"},"thumbnailUrl":"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2013\/05\/0-summary-alkylation-of-alkyynes-through-deprotonation-and-reaction-with-alkyl-halides.gif","keywords":["acidity","alkynes","SN2","sp","substitution","synthesis"],"articleSection":["Alkyne Reactions"],"inLanguage":"en-US","potentialAction":[{"@type":"CommentAction","name":"Comment","target":["https:\/\/www.masterorganicchemistry.com\/2013\/05\/01\/acetylide-formation-alkylation\/#respond"]}]},{"@type":"WebPage","@id":"https:\/\/www.masterorganicchemistry.com\/2013\/05\/01\/acetylide-formation-alkylation\/","url":"https:\/\/www.masterorganicchemistry.com\/2013\/05\/01\/acetylide-formation-alkylation\/","name":"Acetylides from Alkynes, and The Substitution Reactions of Acetylides","isPartOf":{"@id":"https:\/\/www.masterorganicchemistry.com\/#website"},"primaryImageOfPage":{"@id":"https:\/\/www.masterorganicchemistry.com\/2013\/05\/01\/acetylide-formation-alkylation\/#primaryimage"},"image":{"@id":"https:\/\/www.masterorganicchemistry.com\/2013\/05\/01\/acetylide-formation-alkylation\/#primaryimage"},"thumbnailUrl":"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2013\/05\/0-summary-alkylation-of-alkyynes-through-deprotonation-and-reaction-with-alkyl-halides.gif","datePublished":"2013-05-01T12:03:07+00:00","dateModified":"2026-04-21T15:45:03+00:00","description":"What are the two most important reactions of alkynes? First, deprotonation to give an acetylide. Then, SN2 of the acetylide with an alkyl halide forming C\u2013C","breadcrumb":{"@id":"https:\/\/www.masterorganicchemistry.com\/2013\/05\/01\/acetylide-formation-alkylation\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/www.masterorganicchemistry.com\/2013\/05\/01\/acetylide-formation-alkylation\/"]}]},{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/www.masterorganicchemistry.com\/2013\/05\/01\/acetylide-formation-alkylation\/#primaryimage","url":"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2013\/05\/0-summary-alkylation-of-alkyynes-through-deprotonation-and-reaction-with-alkyl-halides.gif","contentUrl":"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2013\/05\/0-summary-alkylation-of-alkyynes-through-deprotonation-and-reaction-with-alkyl-halides.gif","width":920,"height":576,"caption":"summary- alkylation of alkyynes through deprotonation and reaction with alkyl halides"},{"@type":"BreadcrumbList","@id":"https:\/\/www.masterorganicchemistry.com\/2013\/05\/01\/acetylide-formation-alkylation\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/www.masterorganicchemistry.com\/"},{"@type":"ListItem","position":2,"name":"Acetylides from Alkynes, And Substitution Reactions of Acetylides"}]},{"@type":"WebSite","@id":"https:\/\/www.masterorganicchemistry.com\/#website","url":"https:\/\/www.masterorganicchemistry.com\/","name":"Master Organic Chemistry","description":"","publisher":{"@id":"https:\/\/www.masterorganicchemistry.com\/#organization"},"potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/www.masterorganicchemistry.com\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-US"},{"@type":"Organization","@id":"https:\/\/www.masterorganicchemistry.com\/#organization","name":"Master Organic Chemistry","url":"https:\/\/www.masterorganicchemistry.com\/","logo":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/www.masterorganicchemistry.com\/#\/schema\/logo\/image\/","url":"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2019\/04\/cutmypic.png","contentUrl":"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2019\/04\/cutmypic.png","width":225,"height":225,"caption":"Master Organic Chemistry"},"image":{"@id":"https:\/\/www.masterorganicchemistry.com\/#\/schema\/logo\/image\/"},"sameAs":["https:\/\/www.facebook.com\/Master-Organic-Chemistry-242610599108055\/"]},{"@type":"Person","@id":"https:\/\/www.masterorganicchemistry.com\/#\/schema\/person\/78d83ec7d02b4b7365bade2cedaef80c","name":"James Ashenhurst","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/secure.gravatar.com\/avatar\/f9e9df435875e5e6b0bdff6b8522a7279d5717644b3efa7299da22c837bf9fcf?s=96&d=retro&r=g","url":"https:\/\/secure.gravatar.com\/avatar\/f9e9df435875e5e6b0bdff6b8522a7279d5717644b3efa7299da22c837bf9fcf?s=96&d=retro&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/f9e9df435875e5e6b0bdff6b8522a7279d5717644b3efa7299da22c837bf9fcf?s=96&d=retro&r=g","caption":"James Ashenhurst"},"description":"Ph.D. 2006, McGill University (James L. Gleason). Postdoctoral Associate, 2008-2010, Massachusetts Institute of Technology (M. Movassaghi). Founder, Master Organic Chemistry, 2010-present.","sameAs":["https:\/\/www.masterorganicchemistry.com\/about\/"],"url":"https:\/\/www.masterorganicchemistry.com\/author\/james\/"}]}},"_links":{"self":[{"href":"https:\/\/www.masterorganicchemistry.com\/wp-json\/wp\/v2\/posts\/7256","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.masterorganicchemistry.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.masterorganicchemistry.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.masterorganicchemistry.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.masterorganicchemistry.com\/wp-json\/wp\/v2\/comments?post=7256"}],"version-history":[{"count":0,"href":"https:\/\/www.masterorganicchemistry.com\/wp-json\/wp\/v2\/posts\/7256\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.masterorganicchemistry.com\/wp-json\/wp\/v2\/media\/35941"}],"wp:attachment":[{"href":"https:\/\/www.masterorganicchemistry.com\/wp-json\/wp\/v2\/media?parent=7256"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.masterorganicchemistry.com\/wp-json\/wp\/v2\/categories?post=7256"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.masterorganicchemistry.com\/wp-json\/wp\/v2\/tags?post=7256"},{"taxonomy":"post_folder","embeddable":true,"href":"https:\/\/www.masterorganicchemistry.com\/wp-json\/wp\/v2\/post_folder?post=7256"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}