{"id":218222,"date":"2025-05-23T11:58:52","date_gmt":"2025-05-23T11:58:52","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=218222"},"modified":"2025-05-23T11:58:55","modified_gmt":"2025-05-23T11:58:55","slug":"r-peaks-and-functional-groups-of-each-spectrum","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/05\/23\/r-peaks-and-functional-groups-of-each-spectrum\/","title":{"rendered":"R peaks and functional groups of each spectrum"},"content":{"rendered":"\n<p>R peaks and functional groups of each spectrum (cyclohexene, trans-bromocyclohexanol, and epoxycyclohexane)Which characteristics peaks (appearance\/disappearance) are consistent with the conversion of each reactant into the product within the 2 step synthesis performed?<\/p>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\"><\/ol>\n\n\n\n<p><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-ast-global-color-1-color\">The Correct Answer and Explanation is:<\/mark><\/strong><\/p>\n\n\n\n<h3 class=\"wp-block-heading\">IR Peaks and Functional Groups:<\/h3>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Cyclohexene<\/strong><br><strong>Key IR Peaks:<\/strong>\n<ul class=\"wp-block-list\">\n<li><strong>C=C Stretch<\/strong> (alkene): ~1640\u20131680 cm\u207b\u00b9<\/li>\n\n\n\n<li><strong>=C\u2013H Stretch<\/strong>: ~3020\u20133100 cm\u207b\u00b9<\/li>\n\n\n\n<li><strong>C\u2013H Stretch (sp\u00b3)<\/strong>: ~2850\u20132960 cm\u207b\u00b9<br><strong>Functional Groups:<\/strong> Alkene (C=C), aliphatic hydrogens<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>trans-Bromocyclohexanol<\/strong><br><strong>Key IR Peaks:<\/strong>\n<ul class=\"wp-block-list\">\n<li><strong>O\u2013H Stretch (alcohol):<\/strong> ~3200\u20133550 cm\u207b\u00b9 (broad)<\/li>\n\n\n\n<li><strong>C\u2013Br Stretch:<\/strong> ~500\u2013700 cm\u207b\u00b9<\/li>\n\n\n\n<li><strong>C\u2013H Stretch (sp\u00b3):<\/strong> ~2850\u20132960 cm\u207b\u00b9<br><strong>Functional Groups:<\/strong> Alcohol (\u2013OH), alkyl bromide (C\u2013Br), no alkene present<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Epoxycyclohexane<\/strong><br><strong>Key IR Peaks:<\/strong>\n<ul class=\"wp-block-list\">\n<li><strong>C\u2013O\u2013C Stretch (epoxide):<\/strong> ~800\u2013950 cm\u207b\u00b9 (ring deformation)<\/li>\n\n\n\n<li><strong>C\u2013H Stretch (sp\u00b3):<\/strong> ~2850\u20132960 cm\u207b\u00b9<\/li>\n\n\n\n<li>Absence of O\u2013H peak<br><strong>Functional Groups:<\/strong> Epoxide ring (cyclic ether), saturated ring<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">Explanation of Peak Changes During 2-Step Synthesis:<\/h3>\n\n\n\n<p>The 2-step synthesis from cyclohexene to epoxycyclohexane involves an <strong>electrophilic addition<\/strong> of bromine and water (forming trans-bromocyclohexanol), followed by <strong>base-promoted intramolecular substitution<\/strong> to form the epoxide.<\/p>\n\n\n\n<p>In <strong>Step 1<\/strong>, cyclohexene&#8217;s alkene peak (~1640 cm\u207b\u00b9) <strong>disappears<\/strong>, indicating the double bond is consumed. A <strong>broad O\u2013H stretch<\/strong> (~3200\u20133550 cm\u207b\u00b9) appears, confirming formation of an alcohol group. A new <strong>C\u2013Br stretch<\/strong> (~500\u2013700 cm\u207b\u00b9) supports the addition of bromine across the former double bond.<\/p>\n\n\n\n<p>In <strong>Step 2<\/strong>, during cyclization, the O\u2013H group reacts with the neighboring carbon bearing the Br, forming a three-membered epoxide ring. This causes the <strong>O\u2013H stretch to disappear<\/strong>, indicating the alcohol is no longer free. The <strong>C\u2013Br peak also disappears<\/strong>, showing bromine has left as a leaving group. A new <strong>epoxide-related C\u2013O\u2013C stretch<\/strong> (800\u2013950 cm\u207b\u00b9) appears, confirming successful epoxide formation.<\/p>\n\n\n\n<p>These IR spectral changes\u2014<strong>disappearance of alkene and alcohol peaks<\/strong>, and <strong>appearance of epoxide-related stretches<\/strong>\u2014provide strong evidence for the successful transformation of cyclohexene through trans-bromocyclohexanol into epoxycyclohexane.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" src=\"https:\/\/learnexams.com\/blog\/wp-content\/uploads\/2025\/05\/image-180.png\" alt=\"\" class=\"wp-image-218223\"\/><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>R peaks and functional groups of each spectrum (cyclohexene, trans-bromocyclohexanol, and epoxycyclohexane)Which characteristics peaks (appearance\/disappearance) are consistent with the conversion of each reactant into the product within the 2 step synthesis performed? The Correct Answer and Explanation is: IR Peaks and Functional Groups: Explanation of Peak Changes During 2-Step Synthesis: The 2-step synthesis from cyclohexene [&hellip;]<\/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-218222","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/218222","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=218222"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/218222\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=218222"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=218222"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=218222"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}