{"id":244293,"date":"2025-07-05T03:38:09","date_gmt":"2025-07-05T03:38:09","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=244293"},"modified":"2025-07-05T03:38:11","modified_gmt":"2025-07-05T03:38:11","slug":"memgbr-2-equiv-2-h3o-ome-oh-ph-ph","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/07\/05\/memgbr-2-equiv-2-h3o-ome-oh-ph-ph\/","title":{"rendered":"MeMgBr (2 equiv:) 2) H3O + OMe OH Ph Ph"},"content":{"rendered":"\n

MeMgBr (2 equiv:) 2) H3O + OMe OH Ph Ph<\/p>\n\n\n\n

The Correct Answer and Explanation is:<\/mark><\/strong><\/p>\n\n\n\n

Here\u2019s the breakdown of the reaction:<\/p>\n\n\n\n

    \n
  1. Grignard Reagent Formation<\/strong>:\n
      \n
    • MeMgBr<\/strong> is a Grignard reagent, typically used to form carbon-carbon bonds. Grignard reagents are prepared by reacting an alkyl or aryl halide (in this case, methyl bromide) with magnesium in an anhydrous solvent like ether.<\/li>\n<\/ul>\n<\/li>\n\n\n\n
    • Reaction with Ester<\/strong>:\n
        \n
      • The “OMe” could represent a methoxy group attached to an ester (i.e., R-COOCH\u2083<\/strong> or something similar), and “Ph” represents a phenyl group. The Grignard reagent (MeMgBr) would attack the carbonyl group of the ester in a nucleophilic addition.<\/li>\n\n\n\n
      • The methyl group (Me) from the Grignard reagent will add to the electrophilic carbonyl carbon, breaking the ester bond, forming a tetrahedral intermediate.<\/li>\n<\/ul>\n<\/li>\n\n\n\n
      • Hydrolysis<\/strong>:\n
          \n
        • After the nucleophilic addition, the intermediate is then hydrolyzed with H\u2083O\u207a<\/strong> (acidic aqueous workup). This protonates the alkoxide to form a hydroxyl group, resulting in an alcohol and the conversion of the ester into a secondary alcohol<\/strong> (in this case, with one of the groups being the methyl group from MeMgBr).<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n\n\n\n

          Mechanism Summary:<\/h3>\n\n\n\n
            \n
          • The Grignard reagent<\/strong> (MeMgBr) attacks the carbonyl carbon<\/strong> of the ester, breaking the ester bond.<\/li>\n\n\n\n
          • The intermediate undergoes hydrolysis<\/strong> (with H\u2083O\u207a) to yield a secondary alcohol<\/strong>.<\/li>\n\n\n\n
          • The OMe group<\/strong> remains attached to the alcohol.<\/li>\n<\/ul>\n\n\n\n

            Example:<\/h4>\n\n\n\n

            If the ester involved is methyl benzoate (PhCOOCH\u2083<\/strong>), the reaction could proceed as:PhCOOCH\u2083+MeMgBr\u2192H\u2083O\u207aPhCH(OMe)CH\u2083\\text{PhCOOCH\u2083} + \\text{MeMgBr} \\xrightarrow{\\text{H\u2083O\u207a}} \\text{PhCH(OMe)CH\u2083}PhCOOCH\u2083+MeMgBrH\u2083O\u207a\u200bPhCH(OMe)CH\u2083<\/p>\n\n\n\n

            This results in 2-methylphenylmethanol<\/strong> after the addition of the methyl group to the phenyl group via Grignard addition and hydrolysis.<\/p>\n\n\n\n

            \"\"<\/figure>\n","protected":false},"excerpt":{"rendered":"

            MeMgBr (2 equiv:) 2) H3O + OMe OH Ph Ph The Correct Answer and Explanation is: Here\u2019s the breakdown of the reaction: Mechanism Summary: Example: If the ester involved is methyl benzoate (PhCOOCH\u2083), the reaction could proceed as:PhCOOCH\u2083+MeMgBr\u2192H\u2083O\u207aPhCH(OMe)CH\u2083\\text{PhCOOCH\u2083} + \\text{MeMgBr} \\xrightarrow{\\text{H\u2083O\u207a}} \\text{PhCH(OMe)CH\u2083}PhCOOCH\u2083+MeMgBrH\u2083O\u207a\u200bPhCH(OMe)CH\u2083 This results in 2-methylphenylmethanol after the addition of the methyl group to the […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[25],"tags":[],"class_list":["post-244293","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/244293","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/comments?post=244293"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/244293\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=244293"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=244293"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=244293"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}