{"id":185259,"date":"2025-01-22T09:45:44","date_gmt":"2025-01-22T09:45:44","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=185259"},"modified":"2025-01-22T09:45:46","modified_gmt":"2025-01-22T09:45:46","slug":"draw-the-product-of-the-e2-reaction-shown-below","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/01\/22\/draw-the-product-of-the-e2-reaction-shown-below\/","title":{"rendered":"Draw the product of the E2 reaction shown below"},"content":{"rendered":"\n

Draw the product of the E2 reaction shown below. Include the correct stereochemistry. Ignore any inorganic byproducts. DBU Draw the E2 Product @ 68% – Br Submit<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

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

To answer this question, let’s consider the key points about the E2 reaction and its stereochemical implications:<\/p>\n\n\n\n

E2 Reaction Overview:<\/strong><\/h3>\n\n\n\n
    \n
  1. Elimination Mechanism:<\/strong> E2 reactions proceed in a single step where the base abstracts a proton from a \u03b2-carbon, and a leaving group (e.g., Br\u207b) departs simultaneously. This results in the formation of a double bond.<\/li>\n\n\n\n
  2. Anti-Periplanar Geometry:<\/strong> For the reaction to proceed efficiently, the \u03b2-hydrogen and leaving group must be in an anti-periplanar (opposite planes, 180\u00b0 apart) conformation.<\/li>\n\n\n\n
  3. Stereochemistry:<\/strong> The product’s configuration depends on the starting molecule’s stereochemistry and anti-periplanar arrangement.<\/li>\n<\/ol>\n\n\n\n
    \n\n\n\n

    Given Reaction:<\/strong><\/h3>\n\n\n\n
      \n
    • Base:<\/strong> DBU (a strong, non-nucleophilic base) favors elimination.<\/li>\n\n\n\n
    • Substrate:<\/strong> A molecule with a bromine atom (-Br) and \u03b2-hydrogens available for elimination.<\/li>\n\n\n\n
    • Focus:<\/strong> Include correct stereochemistry in the product.<\/li>\n<\/ul>\n\n\n\n
      \n\n\n\n

      Steps to Determine the Product:<\/strong><\/h3>\n\n\n\n
        \n
      1. Identify the \u03b2-Hydrogens:<\/strong> Locate the hydrogen(s) on the \u03b2-carbon (next to the carbon with -Br).<\/li>\n\n\n\n
      2. Ensure Anti-Periplanar Geometry:<\/strong> Rotate the molecule (if needed) to align the \u03b2-hydrogen and -Br anti-periplanar. This geometry ensures the correct stereochemical outcome.<\/li>\n\n\n\n
      3. Form the Double Bond:<\/strong> Remove the \u03b2-hydrogen and -Br to create a \u03c0-bond between the \u03b1 and \u03b2-carbons.<\/li>\n<\/ol>\n\n\n\n
        \n\n\n\n

        Answer with Explanation:<\/strong><\/h3>\n\n\n\n

        The product is an alkene<\/strong> with a trans configuration if the starting material allows it. Here’s why:<\/p>\n\n\n\n

          \n
        • DBU abstracts the \u03b2-hydrogen anti-periplanar to -Br.<\/li>\n\n\n\n
        • The double bond forms between the \u03b1 and \u03b2-carbons, with substituents positioned to minimize steric hindrance, favoring the more stable trans configuration.<\/li>\n<\/ul>\n\n\n\n

          I will draw the product with correct stereochemistry for clarity.<\/p>\n\n\n\n

          It seems I can’t directly render the chemical structure here, but I’ll describe it in detail instead.<\/p>\n\n\n\n

          Structure of the Product:<\/strong><\/h3>\n\n\n\n

          Assume a starting substrate like 2-bromobutane:<\/p>\n\n\n\n

            \n
          1. The bromine is on the second carbon (C2).<\/li>\n\n\n\n
          2. The \u03b2-hydrogens are on the adjacent carbons (C1 and C3).<\/li>\n<\/ol>\n\n\n\n

            Upon elimination:<\/p>\n\n\n\n

              \n
            • The double bond forms between C2 and C3.<\/li>\n\n\n\n
            • Substituents on C2 and C3 adopt a trans configuration (opposite sides of the double bond), yielding trans-2-butene<\/strong> as the product.<\/li>\n<\/ul>\n\n\n\n
              \n\n\n\n

              Conclusion:<\/strong><\/h3>\n\n\n\n

              The E2 reaction yields a stereoselective product favoring the trans alkene due to its greater stability. The use of a strong base like DBU ensures efficient elimination with the correct anti-periplanar alignment of the \u03b2-hydrogen and bromine.<\/p>\n","protected":false},"excerpt":{"rendered":"

              Draw the product of the E2 reaction shown below. Include the correct stereochemistry. Ignore any inorganic byproducts. DBU Draw the E2 Product @ 68% – Br Submit The Correct Answer and Explanation is : To answer this question, let’s consider the key points about the E2 reaction and its stereochemical implications: E2 Reaction Overview: Given […]<\/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-185259","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/185259","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=185259"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/185259\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=185259"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=185259"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=185259"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}