{"id":218264,"date":"2025-05-23T13:48:23","date_gmt":"2025-05-23T13:48:23","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=218264"},"modified":"2025-05-23T13:48:25","modified_gmt":"2025-05-23T13:48:25","slug":"determine-the-intermediates-and-the-product-for-the-following-reaction","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/05\/23\/determine-the-intermediates-and-the-product-for-the-following-reaction\/","title":{"rendered":"Determine the intermediates and the product for the following reaction."},"content":{"rendered":"\n

Determine the intermediates and the product for the following reaction. (11 (CH)Cul Br2 CHyCH2OH LiBr LizCO,, DMF 2) H2O CHC [11 (CH,) Cui 21 H2O KOC(CHjh<\/p>\n\n\n\n

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

To accurately determine the intermediates and the product of the given reaction, we first need to parse and understand the reaction conditions and reagents:<\/p>\n\n\n\n

\n\n\n\n

Reaction Summary (Interpreted Format):<\/strong><\/h3>\n\n\n\n
    \n
  1. Starting Material:<\/strong> 11-bromoalkane (likely a compound with a Br at the end of a long carbon chain).<\/li>\n\n\n\n
  2. Reagents in Step 1:<\/strong><\/li>\n<\/ol>\n\n\n\n
      \n
    • (CH\u2083)\u2082CuLi (Gilman Reagent)<\/strong>: Organocuprate<\/li>\n\n\n\n
    • Br\u2082<\/strong><\/li>\n\n\n\n
    • CH\u2083CH\u2082OH<\/strong> (ethanol)<\/li>\n\n\n\n
    • LiBr<\/strong><\/li>\n\n\n\n
    • Li\u2082CO\u2083<\/strong> (lithium carbonate)<\/li>\n\n\n\n
    • DMF (dimethylformamide)<\/strong><\/li>\n<\/ul>\n\n\n\n
        \n
      1. Step 2:<\/strong><\/li>\n<\/ol>\n\n\n\n
          \n
        • H\u2082O<\/strong><\/li>\n\n\n\n
        • CHCl\u2083<\/strong> (chloroform)<\/li>\n<\/ul>\n\n\n\n
            \n
          1. Step 3:<\/strong><\/li>\n<\/ol>\n\n\n\n
              \n
            • KOC(CH\u2083)\u2083<\/strong> (potassium tert-butoxide)<\/li>\n<\/ul>\n\n\n\n
              \n\n\n\n

              Likely Reaction Pathway:<\/strong><\/h3>\n\n\n\n

              Step 1: Substitution via Gilman Reagent<\/strong><\/h4>\n\n\n\n

              Organocuprates (R\u2082CuLi) perform nucleophilic substitution (especially SN2) on primary alkyl halides (R\u2013Br). The Gilman reagent (CH\u2083)\u2082CuLi substitutes the Br with a methyl group.<\/p>\n\n\n\n

              Intermediate 1:<\/strong> 11-methylalkane (R\u2013CH\u2083 replacing R\u2013Br)<\/p>\n\n\n\n

              Step 2: \u03b1-Halogenation or Hydrolysis<\/strong><\/h4>\n\n\n\n

              The use of Br\u2082 in ethanol, water, and carbonate in DMF indicates oxidative conditions\u2014possibly forming an \u03b1-bromo ketone or alcohol from a methyl-substituted ketone.<\/p>\n\n\n\n

              Alternatively, the organocuprate could add to a compound to form a ketone intermediate that hydrolyzes in water (step 2) to give a carbonyl-containing intermediate<\/strong>.<\/p>\n\n\n\n

              Intermediate 2:<\/strong> Likely a ketone or alcohol at the terminal end.<\/p>\n\n\n\n

              Step 3: E2 Elimination<\/strong><\/h4>\n\n\n\n

              KOC(CH\u2083)\u2083 (a strong, bulky base) promotes E2 elimination, especially from secondary or tertiary alcohols or alkyl halides, favoring formation of alkenes.<\/p>\n\n\n\n

              Final Product:<\/strong> Internal alkene<\/strong> (possibly a terminal or internal double bond depending on the location of the leaving group).<\/p>\n\n\n\n

              \n\n\n\n

              Explanation (300 words):<\/strong><\/h3>\n\n\n\n

              This reaction proceeds through organocuprate chemistry, nucleophilic substitution, oxidation\/hydrolysis, and elimination steps. In the first step, the Gilman reagent (CH\u2083)\u2082CuLi, a lithium diorganocuprate, attacks the alkyl halide (a bromoalkane) in a typical SN2 reaction, replacing the bromine atom with a methyl group. This yields an alkane with a new C\u2013C bond.<\/p>\n\n\n\n

              In the second step, the reaction mixture contains Br\u2082, ethanol, lithium bromide, and lithium carbonate in DMF. This indicates oxidative conditions, likely converting the methylated intermediate into a carbonyl compound such as a ketone. Water is then used to hydrolyze any intermediates to stabilize the ketone or alcohol. The presence of CHCl\u2083 could be inert or used as a solvent.<\/p>\n\n\n\n

              In the final step, treatment with potassium tert-butoxide\u2014a strong, non-nucleophilic base\u2014leads to E2 elimination. This base preferentially abstracts \u03b2-hydrogens anti-periplanar to leaving groups (such as Br or OH), leading to the formation of a double bond (alkene).<\/p>\n\n\n\n

              Overall, the transformation starts with a halogenated alkane, installs a methyl group through organocuprate substitution, undergoes oxidative conversion to a carbonyl compound, and finally forms an alkene via elimination. Each step highlights classic reactivity patterns: SN2 substitution by Gilman reagents, oxidation\/hydrolysis of alkyl chains, and strong base-induced elimination. The product is likely a substituted alkene (internal), derived from the original bromoalkane via C\u2013C bond formation and elimination.<\/p>\n\n\n\n

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

              Determine the intermediates and the product for the following reaction. (11 (CH)Cul Br2 CHyCH2OH LiBr LizCO,, DMF 2) H2O CHC [11 (CH,) Cui 21 H2O KOC(CHjh The Correct Answer and Explanation is: To accurately determine the intermediates and the product of the given reaction, we first need to parse and understand the reaction conditions and […]<\/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-218264","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/218264","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=218264"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/218264\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=218264"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=218264"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=218264"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}