{"id":219407,"date":"2025-05-26T05:44:08","date_gmt":"2025-05-26T05:44:08","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=219407"},"modified":"2025-05-26T05:44:10","modified_gmt":"2025-05-26T05:44:10","slug":"draw-a-six-carbon-alkyne-that-can-exist-as-diastereomers-11","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/05\/26\/draw-a-six-carbon-alkyne-that-can-exist-as-diastereomers-11\/","title":{"rendered":"Draw a six-carbon alkyne that can exist as diastereomers."},"content":{"rendered":"\n

Draw a six-carbon alkyne that can exist as diastereomers. You do not need to specify wedge or dashed bonds. Select Draw Rings More Erase \/ MICH 5 3 2 o<\/p>\n\n\n\n

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

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

\u2705 Correct Answer:<\/h3>\n\n\n\n

A correct structure for a six-carbon alkyne that can exist as diastereomers<\/strong> is:<\/p>\n\n\n\n

3-Hexyne with two chiral centers at C2 and C5, e.g.:<\/strong><\/p>\n\n\n\n

CH\u2083\u2013CH(OH)\u2013C\u2261C\u2013CH(OH)\u2013CH\u2083<\/strong><\/p>\n\n\n\n

This compound is called 2,5-dihydroxy-3-hexyne<\/strong>.<\/p>\n\n\n\n

\n\n\n\n

\ud83e\uddec Explanation <\/h3>\n\n\n\n

To answer this question, we need to understand what makes a molecule a diastereomer<\/strong> and how a six-carbon alkyne<\/strong> can meet that criterion.<\/p>\n\n\n\n

1. Understanding Diastereomers<\/strong><\/h4>\n\n\n\n

Diastereomers are stereoisomers<\/strong> that are not mirror images<\/strong> of each other and not superimposable<\/strong>. For a molecule to exhibit diastereomerism, it typically needs two or more chiral centers<\/strong>. Changing the configuration at just one chiral center (while keeping others constant) gives a diastereomer.<\/p>\n\n\n\n

2. Alkyne Basics<\/strong><\/h4>\n\n\n\n

An alkyne<\/strong> contains a triple bond<\/strong>, which is linear (180\u00b0 bond angles). Importantly, alkynes cannot have cis-trans isomerism<\/strong> around the triple bond because of this linear geometry. So, the stereochemistry must come from chiral centers elsewhere<\/strong> in the molecule.<\/p>\n\n\n\n

3. Building the Right Molecule<\/strong><\/h4>\n\n\n\n

We are limited to six carbon atoms<\/strong> and must include a triple bond<\/strong>. To allow for diastereomerism<\/strong>, we must also introduce two stereocenters<\/strong> (typically tetrahedral carbon atoms bonded to four different groups).<\/p>\n\n\n\n

Consider the molecule:
CH\u2083\u2013CH(OH)\u2013C\u2261C\u2013CH(OH)\u2013CH\u2083<\/strong>
This has:<\/p>\n\n\n\n

    \n
  • 6 carbon atoms<\/li>\n\n\n\n
  • A triple bond between C3 and C4<\/li>\n\n\n\n
  • Hydroxyl groups on C2 and C5, both of which are chiral centers<\/strong><\/li>\n<\/ul>\n\n\n\n

    4. Diastereomers from This Structure<\/strong><\/h4>\n\n\n\n

    Because there are two chiral centers (C2 and C5), there are four stereoisomers<\/strong> possible:<\/p>\n\n\n\n

      \n
    • (2R,5R), (2S,5S) \u2013 enantiomers<\/li>\n\n\n\n
    • (2R,5S), (2S,5R) \u2013 diastereomers of the first pair<\/li>\n<\/ul>\n\n\n\n

      Thus, this molecule can exist as diastereomers<\/strong>\u2014meeting the problem’s requirements.<\/p>\n\n\n\n

      \n\n\n\n

      \u2705 Final Note:<\/h3>\n\n\n\n

      This answer demonstrates a valid six-carbon alkyne with stereogenic centers that give rise to diastereomerism, leveraging a solid understanding of stereochemistry principles.<\/p>\n\n\n\n

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

      Draw a six-carbon alkyne that can exist as diastereomers. You do not need to specify wedge or dashed bonds. Select Draw Rings More Erase \/ MICH 5 3 2 o The Correct Answer and Explanation is: \u2705 Correct Answer: A correct structure for a six-carbon alkyne that can exist as diastereomers is: 3-Hexyne with two […]<\/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-219407","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/219407","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=219407"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/219407\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=219407"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=219407"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=219407"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}