{"id":9356,"date":"2016-01-13T15:42:19","date_gmt":"2016-01-13T20:42:19","guid":{"rendered":"https:\/\/www.masterorganicchemistry.com\/?p=9356"},"modified":"2026-05-07T06:05:17","modified_gmt":"2026-05-07T11:05:17","slug":"synthesis-using-grignard-reagents-1","status":"publish","type":"post","link":"https:\/\/www.masterorganicchemistry.com\/2016\/01\/13\/synthesis-using-grignard-reagents-1\/","title":{"rendered":"Synthesis Problems Involving Grignard Reagents"},"content":{"rendered":"<p><strong>Grignard Practice Problems: Synthesis Exercises Involving Grignard Reagents<\/strong><\/p>\n<ul>\n<li>Grignard reagents add <strong>once<\/strong> to aldehydes to give secondary alcohols and\u00a0also add <strong>once\u00a0<\/strong>to ketones to give tertiary alcohols.<\/li>\n<li>Esters react\u00a0<strong>twice<\/strong> with Grignard reagents to give tertiary alcohols which contain two identical R groups.<\/li>\n<\/ul>\n<p>So when working backwards in a synthesis problem involving Grignard reagents:<\/p>\n<ul>\n<li>Secondary alcohols can be produced <strong>two<\/strong> possible ways, depending on which C-C bond is formed by the Grignard reagent.<\/li>\n<li>Tertiary alcohols containing three different R groups can be produced in <strong>three<\/strong> possible ways, via three possible ketone precursors<\/li>\n<li>Tertiary alcohols where at least two groups are the same can be produced from an <strong>ester <\/strong>in only <strong>one way<\/strong> &#8211; the two groups that are the same will originate as Grignard reagents, and the other R group will be a part of the ester.<\/li>\n<\/ul>\n<p><img fetchpriority=\"high\" decoding=\"async\" class=\"alignnone wp-image-35161\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2023\/07\/0-summary-for-planning-synthesis-of-alcohols-from-aldehydes-ketones-and-esters.gif\" alt=\"summary for planning synthesis of alcohols from aldehydes ketones and esters\" width=\"640\" height=\"594\" \/><\/a><\/p>\n<p><strong>Table of Contents<\/strong><\/p>\n<ol>\n<li><a href=\"#one\">Solving Synthesis Problems Involving Grignard Reagents<\/a><\/li>\n<li><a href=\"#two\">Three Key Reactions of Grignard Reagents<\/a><\/li>\n<li><a href=\"#three\">Problem 1: Learning To Think In Reverse<\/a><\/li>\n<li><a href=\"#four\">Problem 2:<\/a><\/li>\n<li><a href=\"#five\">What About Esters? (And Problem 3)<\/a><\/li>\n<li><a href=\"#six\">Summary: Grignard Practice Problems<\/a><\/li>\n<li><a href=\"#notes\">Notes<\/a><\/li>\n<li><a href=\"#quizzes\">Quiz Yourself!<\/a><\/li>\n<\/ol>\n<hr \/>\n<h2><a id=\"one\"><\/a>1. Solving Synthesis Problems Involving Grignard Reagents<\/h2>\n<p>Now that we&#8217;ve covered some of the <a href=\"https:\/\/www.masterorganicchemistry.com\/2015\/12\/10\/reactions-of-grignard-reagents\/\">most important reactions of Grignard reagents<\/a>, it&#8217;s time to actually apply this knowledge to practical matters. And by practical matters, I mean <strong>synthesis.\u00a0<\/strong><\/p>\n<p>After all, the point of learning each of the reactions in organic chemistry is that they&#8217;re useful <em>tools<\/em> for forging\u00a0and breaking certain bonds. Just like a carpenter might use a hammer, nails, screwdrivers and various saws to build a table, organic chemists apply the &#8220;tools&#8221; of organic reactions toward some kind of goal &#8211; building a molecule from simpler components, for example.<\/p>\n<p>A skilled carpenter\u00a0can imagine\u00a0a finished table and then think backwards to what tools to use to build it from simpler parts. Similarly, organic chemists must be able to envision how a complex molecule can be made through a <strong>sequence of\u00a0\u00a0reactions<\/strong>.<\/p>\n<p>In this post, we&#8217;ll \u00a0go through three exercises that show how we can &#8220;think backwards&#8221; from the product of a Grignard reaction to its starting materials.<\/p>\n<p>So let&#8217;s get started!<\/p>\n<p><img decoding=\"async\" class=\"alignnone wp-image-15351\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2019\/12\/1-example-grignard-synthesis-how-would-you-synthesize-using-Grignard.gif\" alt=\"example grignard synthesis how would you synthesize using Grignard\" width=\"600\" height=\"224\" \/><\/p>\n<p>How do we answer a question like this?<\/p>\n<p>Break it down into parts, of course! We&#8217;ll tackle A, B, and C in turn.<\/p>\n<p>Here&#8217;s our plan.<\/p>\n<p>First, we&#8217;ll look at what we know about Grignards in the<strong> forward<\/strong> direction, and then use that information to <strong>work backwards.<\/strong> To take a simple example, if you know that 3 + 4 = 7, then you can work backwards to figure out what number must be subtracted from 7 to give you 3. \u00a0It&#8217;s the same idea, as we&#8217;ll see.<\/p>\n<h2><a id=\"two\"><\/a>2. Three Key Reactions of Grignard Reagents<\/h2>\n<p>Here\u2019s three key reactions of Grignards we learned in a <a href=\"https:\/\/www.masterorganicchemistry.com\/2015\/12\/10\/reactions-of-grignard-reagents\/\">previous post<\/a>: addition to aldehydes, addition to ketones, and addition to esters.<\/p>\n<p><img decoding=\"async\" class=\"alignnone wp-image-15352\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2019\/12\/2-three-key-reactions-of-grignard-reagents-addition-to-aldehydes-ketones-and-esters.gif\" alt=\"three key reactions of grignard reagents addition to aldehydes ketones and esters\" width=\"600\" height=\"547\" \/><\/p>\n<p>Note that in each case we&#8217;re forming C-C and breaking C-O \u00a0as well as forming O-H. In the case of the ester, the Grignard actually adds twice &#8211; a point that&#8217;s important for planning, as we&#8217;ll see.<\/p>\n<h2><a id=\"three\"><\/a>3. Problem 1: Learning To Work &#8220;In Reverse&#8221;<\/h2>\n<p>Let\u2019s look at the first molecule, \u00a02-pentanol.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-15353\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2019\/12\/3-working-backwards-from-pentan-2-ol-to-consider-how-to-synthesize-using-a-grignard-reagent.gif\" alt=\"working backwards from pentan-2-ol to consider how to synthesize using a grignard reagent\" width=\"600\" height=\"142\" \/><\/p>\n<p>Let&#8217;s start with the obvious. It\u2019s a <a href=\"https:\/\/www.masterorganicchemistry.com\/2010\/06\/16\/1-2-3-4\/\"><strong>secondary alcohol<\/strong><\/a>, as the carbon attached to OH is in turn attached to two other carbons. Looking at our list of three reactions above, we know that secondary alcohols can be made through the <strong>addition of Grignard reagents to aldehydes.<\/strong><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-15354\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2019\/12\/4-general-pattern-for-a-grignard-reaction-making-a-secondary-alcohol-goes-back-to-grignard-plus-aldehyde.gif\" alt=\"general pattern for a grignard reaction making a secondary alcohol goes back to grignard plus aldehyde\" width=\"600\" height=\"204\" \/><\/p>\n<p>Again, note that we form C-C and O-H, and break C-O (\u03c0).<\/p>\n<p>Now let&#8217;s ask: what if we were to wave a magic wand, and make this reaction act in reverse? What bonds would form and break?<\/p>\n<p>We&#8217;d be\u00a0<strong>breaking\u00a0<\/strong>C-C and O-H, and\u00a0<strong>forming\u00a0<\/strong>C-O (\u03c0). Since this isn&#8217;t a &#8220;real&#8221; reaction, we use a special open-ended arrow called a &#8220;retrosynthesis arrow&#8221; to show that this is a &#8220;planned&#8221; reaction rather than an actual one.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-15355\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2019\/12\/5-imagining-a-grignard-reaction-in-reverse-from-a-secondary-alcohol-going-to-an-aldehyde-plus-grignard-reagent.gif\" alt=\"imagining a grignard reaction in reverse from a secondary alcohol going to an aldehyde plus grignard reagent\" width=\"600\" height=\"251\" \/><\/p>\n<p>Getting back to that earlier comment about subtraction: if you know that<\/p>\n<p>5 + 8 = 13<\/p>\n<p>and are then asked\u00a0&#8220;what number must be\u00a0removed from 13 to give 5 ?&#8221;<\/p>\n<p>you&#8217;d just have\u00a0rearrange the equation like this:<\/p>\n<p>5 = 13 -8<\/p>\n<p>Of course, you&#8217;re very familiar with subtraction by now, but your 1st grade self probably started by thinking it was tricky. Likewise, working backwards in the context of chemical reactions is a new thing for many people. It takes practice to apply!<\/p>\n<p>Getting back to 2-pentanol:\u00a0as you might have noticed, there\u2019s actually 2 ways to go about looking at this reaction in the reverse reaction, since there are\u00a0<strong>two\u00a0<\/strong>different C-C bonds (let&#8217;s call <strong>A<\/strong> and <strong>B<\/strong>) that we could break to give an aldehyde and a Grignard.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-15356\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2019\/12\/6-two-potentially-different-syntheses-of-a-secondary-alcohol-using-a-grignard-reaction-with-an-aldehyde.gif\" alt=\"two potentially different syntheses of a secondary alcohol using a grignard reaction with an aldehyde\" width=\"600\" height=\"314\" \/><\/p>\n<ul>\n<li>Breaking bond A (retrosynthetically) gives us butanal and methyl Grignard.<\/li>\n<li>Breaking bond B (retrosynthetically) gives us ethanal and propyl Grignard.<\/li>\n<\/ul>\n<p>There&#8217;s no wrong answer here: they&#8217;re actually equally good.<\/p>\n<p>After each Grignard reaction we need to do a mildly acidic workup so that we end up with the neutral alcohol. So in the forward direction we can go:<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-15357\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2019\/12\/7-once-the-grignard-is-planned-in-the-reverse-direction-now-plan-grignard-plus-aldehyde-in-the-forward-direction.gif\" alt=\"once the grignard is planned in the reverse direction now plan grignard plus aldehyde in the forward direction\" width=\"600\" height=\"267\" \/><\/p>\n<p><span style=\"color: #993366;\"><em>[See that I switched something around there: I made the second Grignard derived from Cl instead of Br . Whether your Grignard is Cl, Br, or I doesn&#8217;t matter &#8211; they all work fine].<\/em><\/span><\/p>\n<h2><strong><a id=\"four\"><\/a>4. Problem 2:<\/strong><\/h2>\n<p>Ready for another one? Let&#8217;s look at B.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-15358\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2019\/12\/8-planning-synthesis-of-tertiary-alcohol-through-grignard-reaction.gif\" alt=\"planning synthesis of tertiary alcohol through grignard reaction\" width=\"600\" height=\"174\" \/><\/p>\n<p>The first observation to make here is that the C attached to OH is itself attached to 3 carbons, so it&#8217;s a\u00a0<strong>tertiary alcohol.\u00a0<\/strong><\/p>\n<p>Going back to what we saw\u00a0about the reactions of Grignards, we can suppose that this might be made through the reaction of a ketone with a Grignard reagent.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-15359\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2019\/12\/9-working-backwards-from-a-tertiary-alcohol-to-ketone-and-grignard-reagent.gif\" alt=\"working backwards from a tertiary alcohol to ketone and grignard reagent\" width=\"600\" height=\"184\" \/><\/p>\n<p>In the previous case, there were 2 different ways to make 2-pentanol. Here, there are <strong>three<\/strong>, because we could either break bonds A, B, or C in the &#8220;reverse&#8221; direction to give us one of 3 different combinations of ketone and Grignard reagent.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-15360\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2019\/12\/10-three-different-pathways-to-synthesize-tertiary-alcohol-from-grignard-and-various-ketones.gif\" alt=\"three different pathways to synthesize tertiary alcohol from grignard and various ketones\" width=\"600\" height=\"449\" \/><\/p>\n<p>All are equally OK! Just for clarity, let&#8217;s look at each of them in the forward direction.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-15361\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2019\/12\/11-forward-direction-planning-synthesis-of-tertiary-alcohol-from-grignard-reaction-with-various-ketones.gif\" alt=\"forward direction planning synthesis of tertiary alcohol from grignard reaction with various ketones\" width=\"600\" height=\"423\" \/><\/p>\n<p>Again, I mixed up the halides with the Grignards here, just for variety. You might also see many different (equivalent) workup conditions for Grignard reactions.<\/p>\n<p><strong>As long as they result in protonating the intermediate alkoxide to give the alcohol, they&#8217;re fine.\u00a0<\/strong><\/p>\n<h2><strong><a id=\"five\"><\/a>5. What About Esters? (And Problem 3)<\/strong><\/h2>\n<p>Now you might be asking: reactions of Grignards with esters also gives tertiary alcohols. Why can&#8217;t we use this here?<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-15362\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2019\/12\/12-tertiary-alcohol-with-two-identical-r-groups-is-a-good-occasion-to-plan-grignard-with-ester.gif\" alt=\"tertiary alcohol with two identical r groups is a good occasion to plan grignard with ester\" width=\"600\" height=\"103\" \/><\/p>\n<p>The problem is that there are <strong>3 different R groups on the tertiary alcohol<\/strong>. Recall that Grignards add <strong>twice<\/strong> to esters. Therefore, if we were to plan to use a Grignard reaction with an ester to make a tertiary alcohol, we&#8217;d need at least 2 identical R groups to be present. The bottom of the image gives some examples.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-15363\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2019\/12\/13-grignard-reagents-add-twice-to-esters-so-it-must-be-a-situation-where-there-are-two-identical-r-groups.gif\" alt=\"grignard reagents add twice to esters so it must be a situation where there are two identical r groups\" width=\"600\" height=\"484\" \/><\/p>\n<p>That bottom example also happens to be a good\u00a0answer to question C, by the way.<\/p>\n<p>C can be made through either addition of cyclohexyl Grignard to an ester, or by 2 different combinations of ketones and Grignard reagents. <span style=\"color: #993366;\"><em>Can you find them? Answer below [<a href=\"#noteone\">Note 1<\/a>].<\/em><\/span><\/p>\n<p>That&#8217;s one of the interesting things about synthesis &#8211; <strong>there are often many different ways to go about solving the same problem<\/strong>. In that respect, it&#8217;s also a bit like carpentry: even two different carpenters building the same table might use a slightly different\u00a0sequence\u00a0of events to make the same thing.<\/p>\n<p>In introductory organic, we don&#8217;t get too picky about whether you pick the most efficient synthesis of a molecule. The key is just being able to get there.<\/p>\n<h2><a id=\"six\"><\/a>6. Summary: Grignard Practice Problems<\/h2>\n<p>The key takeaway for this post is to\u00a0<strong>get in the habit of looking at reactions in the backwards direction as well as in the forward direction.\u00a0<\/strong>If you know the bonds that form and break in the forward direction, you can apply the reverse to &#8220;retrosynthetically&#8221; work backwards to its starting materials.<\/p>\n<p>This is yet another reason why I harp on &#8220;what bonds form, what bonds break?&#8221; as the most important question you should ask yourself when you learn a new reaction.<\/p>\n<p>In the next post we&#8217;ll look at a few more Grignard synthesis problems, but throw in a new twist &#8211; a reaction of alcohols we&#8217;ve already learned about called \u00a0oxidation. This will allow us to build up even more complex products from simpler precursors using the Grignard reaction.<\/p>\n<p><strong>Next Post: <a href=\"https:\/\/www.masterorganicchemistry.com\/2016\/01\/19\/grignard-reactions-and-synthesis-2\/\">Grignard Reactions and Synthesis (2)\u00a0<\/a><\/strong><\/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\/2016\/01\/19\/grignard-reactions-and-synthesis-2\/\" class=\"\"><span>Grignard Reactions And Synthesis (2)<\/span><\/a><\/li><li><a href=\"https:\/\/www.masterorganicchemistry.com\/2015\/11\/09\/synthesis-of-grignard-and-organolithium-reagents\/\" class=\"\"><span>Formation of Grignard and Organolithium Reagents<\/span><\/a><\/li><li><a href=\"https:\/\/www.masterorganicchemistry.com\/2015\/12\/16\/protecting-groups-in-grignard-reactions\/\" class=\"\"><span>Protecting Groups In Grignard Reactions<\/span><\/a><\/li><li><a href=\"https:\/\/www.masterorganicchemistry.com\/2011\/05\/06\/nucleophilic-acyl-substitution\/\" class=\"\"><span>Nucleophilic Acyl Substitution (With Negatively Charged Nucleophiles)<\/span><\/a><\/li><li><a href=\"https:\/\/www.masterorganicchemistry.com\/2015\/12\/10\/reactions-of-grignard-reagents\/\" class=\"\"><span>Reactions of Grignard Reagents<\/span><\/a><\/li><li><a href=\"https:\/\/www.masterorganicchemistry.com\/2016\/01\/13\/synthesis-using-grignard-reagents-1\/\" class=\"\"><span>Grignard Practice Problems (MOC Membership)<\/span><\/a><\/li><\/ul><\/div>\n<p><strong><a id=\"noteone\"><\/a>Note 1.\u00a0<\/strong> The answer to how to make\u00a0<strong>C<\/strong> from the reaction of a ketone with a Grignard reagent.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-15364\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/2019\/12\/F1-answer-for-how-to-make-tertiary-alcohol-from-a-ketone-with-a-grignard-reagent.gif\" alt=\"answer for how to make tertiary alcohol from a ketone with a grignard reagent\" width=\"600\" height=\"298\" \/><\/p>\n<hr \/>\n<h2><a id=\"quizzes\"><\/a>Quiz Yourself!<\/h2>\n\n<p class=\"p1\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-26714\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-previews\/0581-Front-Image-Only.png\" alt=\"\" width=\"640\" height=\"616\" \/><\/p>\n<p><a href=\"https:\/\/www.masterorganicchemistry.com\/moc-membership\/\"><strong>Become a\u00a0 MOC member<\/strong><\/a> to see the clickable quiz with answers on the back. <\/p>\n\n<p class=\"p1\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-26714\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-previews\/0582-Front-Image-Only.png\" alt=\"\" width=\"640\" height=\"616\" \/><\/p>\n<p><a href=\"https:\/\/www.masterorganicchemistry.com\/moc-membership\/\"><strong>Become a\u00a0 MOC member<\/strong><\/a> to see the clickable quiz with answers on the back. <\/p>\n\n<p class=\"p1\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-26714\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-previews\/0583-Front-Image-Only.png\" alt=\"\" width=\"640\" height=\"616\" \/><\/p>\n<p><a href=\"https:\/\/www.masterorganicchemistry.com\/moc-membership\/\"><strong>Become a\u00a0 MOC member<\/strong><\/a> to see the clickable quiz with answers on the back. <\/p>\n\n<p class=\"p1\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-26714\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-previews\/0584-Front-Image-Only.png\" alt=\"\" width=\"640\" height=\"616\" \/><\/p>\n<p><a href=\"https:\/\/www.masterorganicchemistry.com\/moc-membership\/\"><strong>Become a\u00a0 MOC member<\/strong><\/a> to see the clickable quiz with answers on the back. <\/p>\n<p><br \/>\n<img loading=\"lazy\" decoding=\"async\" class=\"wp-image-36214 aligncenter\" src=\"https:\/\/www.masterorganicchemistry.com\/wp-content\/uploads\/quiz-previews\/1467-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\/1468-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\/2402-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\/2336-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>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Grignard Practice Problems: Synthesis Exercises Involving Grignard Reagents Grignard reagents add once to aldehydes to give secondary alcohols and\u00a0also add once\u00a0to ketones to give tertiary <\/p>\n","protected":false},"author":1,"featured_media":35161,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[1102],"tags":[583,346,215,1085,822,352,1087,1086],"post_folder":[],"class_list":["post-9356","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-organometallics","tag-grignard","tag-grignard-reagents","tag-grignards","tag-primary-alcohols","tag-secondary-alcohols","tag-synthesis","tag-synthetic-planning","tag-tertiary-alcohols"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.7 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ 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