chemistry-class-12-unit-13-chapter-04-nitrogen-containing-organic-compounds-l-4-5-yo2axycxrsy

<p><Success style="float:center;text-align:center;font-size:28px;"> <B>Nitrogen containing organic compounds Lecture-4</B></Success></p>
<p><primary style="float:center;text-align:center;font-size:24px;"> <B>Stereochemistry</B></primary></p>
<hr>
<main>
<div style='float: left; width:100%;font-size:22px;text-align:left'>
<ul>
<li>The properties of many drugs depends on their stereochemistry</li>
</ul>
</div>
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<img src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/f6082024-f449-4a89-635d-3c50b75b5900/public" width="50%">

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</main>
<hr>
<footer style="font-size:18px;"> <span style="color:blue">Stereochemistry</span> $\rightarrow$ Nitrogen chirality center $\rightarrow$ Ambident nucleophile $\rightarrow$ Reaction $\rightarrow$ Discovery of sulfanilamide $\rightarrow$ Proto alkaloids $\rightarrow$ Classification of alkaloids $\rightarrow$ Nicotine $\rightarrow$ Arecoline $\rightarrow$ Lobeline $\rightarrow$ The hofmann elimination $\rightarrow$ Regioselectivity in the hofmann elimination $\rightarrow$ The cope elimination $\rightarrow$ Reaction </footer>

<p><Success style="float:center;text-align:center;font-size:28px;"> <B>Nitrogen containing organic compounds Lecture-4</B></Success></p>
<p><primary style="float:center;text-align:center;font-size:24px;"> <B>Ambident nucleophile</B></primary></p>
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<main>
<div style='float: left; width:100%;font-size:22px;text-align:left'>
</div>
<ul>
<li>Nucleophiles which have more than one (generally two) suitable atoms through which they can attack the substrate</li>
</ul>
</div>
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<img src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/bdf74a3e-084c-4788-689a-c58d27051d00/public" width="50%">
</div>
<div style='float: right; width:00%;'>
<p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-13-chapter-04-nitrogen-containing-organic-compounds-l-4_5-yo2axycxrsy-026-0622.8.jpg"></p>
</div>
</main>
<hr>
<footer style="font-size:18px;"> Stereochemistry $\rightarrow$ Nitrogen chirality center $\rightarrow$ <span style="color:blue">Ambident nucleophile</span> $\rightarrow$ Reaction $\rightarrow$ Discovery of sulfanilamide $\rightarrow$ Proto alkaloids $\rightarrow$ Classification of alkaloids $\rightarrow$ Nicotine $\rightarrow$ Arecoline $\rightarrow$ Lobeline $\rightarrow$ The hofmann elimination $\rightarrow$ Regioselectivity in the hofmann elimination $\rightarrow$ The cope elimination $\rightarrow$ Reaction </footer>

<p><Success style="float:center;text-align:center;font-size:28px;"> <B>Nitrogen containing organic compounds Lecture-4</B></Success></p>
<p><primary style="float:center;text-align:center;font-size:24px;"> <B>Reaction</B></primary></p>
<hr>
<main>
<div style='float: left; width:100%;font-size:22px;text-align:left'>
<ul>
<li>
<p>R Br + AgCN $\overset{slow}{\longrightarrow}$ AgBr $\downarrow+ [R^{+} + CN^-] \overset{fast}{\longrightarrow}$
$R-N^(+) \equiv C^(-) \quad ; \quad S_N 1$</p>
</li>
<li>
<p>R$-$ Br + NaCN ${\rightarrow}$ $\underset{TS}{\underset{}{| \overset{\delta -}{NC}  — R — \overset{\delta +}{Br} |}}$ $\rightarrow$ $R-CN \quad ;\quad S_N2$</p>
</li>
<li>
<p>$\mathrm{Ag}^{+}$ promotes the formation of $\mathrm{R}^{+}$ by the formation of $ \mathrm{AgX} \hspace{1mm}  \mathrm{ppt}$</p>
</li>
<li>
<p>$Nu^-$ attacks from the side in which it has more electronegative atom</p>
</li>
</ul>
</div>
</main>
<hr>
<footer style="font-size:18px;"> Stereochemistry $\rightarrow$ Nitrogen chirality center $\rightarrow$ Ambident nucleophile $\rightarrow$ <span style="color:blue">Reaction</span> $\rightarrow$ Discovery of sulfanilamide $\rightarrow$ Proto alkaloids $\rightarrow$ Classification of alkaloids $\rightarrow$ Nicotine $\rightarrow$ Arecoline $\rightarrow$ Lobeline $\rightarrow$ The hofmann elimination $\rightarrow$ Regioselectivity in the hofmann elimination $\rightarrow$ The cope elimination $\rightarrow$ Reaction </footer>

<p><Success style="float:center;text-align:center;font-size:28px;"> <B>Nitrogen containing organic compounds Lecture-4</B></Success></p>
<p><primary style="float:center;text-align:center;font-size:24px;"> <B>Reaction</B></primary></p>
<hr>
<main>
<div style='float: left; width:100%;font-size:22px;text-align:left'>
<ul>
<li>
<p>$\mathrm{Na}^{+}$ does not show such promotion for the formation of $\mathrm{R}^{+}$</p>
</li>
<li>
<p>Nu attack takes place by the end which has more polarisable atom</p>
</li>
</ul>
<p>$\mathrm{R}-\mathrm{Br}+\mathrm{AgNO}_2$
$\xrightarrow{\text { slow }}$ $\mathrm{AgBr} \mid+\mathrm{R}^{(1)}+\left[\mathrm{NO}_2\right] \xrightarrow{\text {fast }}\mathrm{R}-\mathrm{O}-\mathrm{N}=\mathrm{O} ; \quad S_N1$</p>
<p>$\mathrm{R}-\mathrm{Br}+\mathrm{NaNO_2}$
$\longrightarrow\left|\begin{array}{lll}\mathrm{O}_2 \hat{\mathrm{N}}  \mathrm{R}  \stackrel{5+}{\mathrm{Br}}\end{array}\right|$
$\longrightarrow \mathrm{RNO}_2 ; \quad S_N2$</p>
</div>
<div style='float: right; width:00%;'>
<p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-13-chapter-04-nitrogen-containing-organic-compounds-l-4_5-yo2axycxrsy-032-0768.0.jpg"></p>
</div>
</main>
<hr>
<footer style="font-size:18px;"> Stereochemistry $\rightarrow$ Nitrogen chirality center $\rightarrow$ Ambident nucleophile $\rightarrow$ <span style="color:blue">Reaction</span> $\rightarrow$ Discovery of sulfanilamide $\rightarrow$ Proto alkaloids $\rightarrow$ Classification of alkaloids $\rightarrow$ Nicotine $\rightarrow$ Arecoline $\rightarrow$ Lobeline $\rightarrow$ The hofmann elimination $\rightarrow$ Regioselectivity in the hofmann elimination $\rightarrow$ The cope elimination $\rightarrow$ Reaction </footer>

<p><Success style="float:center;text-align:center;font-size:28px;"> <B>Nitrogen containing organic compounds Lecture-4</B></Success></p>
<p><primary style="float:center;text-align:center;font-size:24px;"> <B>Reaction</B></primary></p>
<hr>
<main>
<div style='float: left; width:60%;font-size:22px;text-align:left'>
<ul>
<li>
<p><strong>Reduction of Nitriles, Oximes, and Amides</strong></p>
</li>
<li>
<p>Reduction of any of these functional groups by catalytic hydrogenation or lithium aluminum hydride $\left(\mathrm{LiAlH}_4\right)$ yields an amine</p>
</li>
</ul>
</div>
<div style='float: right; width:40%;'>
<img src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/078e109b-4f8f-417f-b95e-425fc691b500/public" width="100%">
</div>
<div style='float: right; width:0%;'>
<p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-13-chapter-04-nitrogen-containing-organic-compounds-l-4_5-yo2axycxrsy-033-1108.8.jpg"></p>
</div>
</main>
<hr>
<footer style="font-size:18px;"> Stereochemistry $\rightarrow$ Nitrogen chirality center $\rightarrow$ Ambident nucleophile $\rightarrow$ <span style="color:blue">Reaction</span> $\rightarrow$ Discovery of sulfanilamide $\rightarrow$ Proto alkaloids $\rightarrow$ Classification of alkaloids $\rightarrow$ Nicotine $\rightarrow$ Arecoline $\rightarrow$ Lobeline $\rightarrow$ The hofmann elimination $\rightarrow$ Regioselectivity in the hofmann elimination $\rightarrow$ The cope elimination $\rightarrow$ Reaction </footer>

<p><Success style="float:center;text-align:center;font-size:28px;"> <B>Nitrogen containing organic compounds Lecture-4</B></Success></p>
<p><primary style="float:center;text-align:center;font-size:24px;"> <B>Discovery of sulfanilamide</B></primary></p>
<hr>
<main>
<div style='float: left; width:60%;font-size:22px;text-align:left'>
<ul>
<li>
<p>In 1936, Ernest Fourneau of the Pasteur Institute in Paris showed that prontosil breaks down in the human body to produce sulfanilamide, the active agent</p>
</li>
<li>
<p>In the following years, many thousands of structural variations of sulfanilamide were synthesized in the search for additional drugs</p>
</li>
</ul>
</div>
<div style='float: right; width:40%;'>
<img src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/3b00d34b-abe3-4c96-5a62-bcd996a20300/public" width="100%">
</div>
<div style='float: right; width:0%;'>
<p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-13-chapter-04-nitrogen-containing-organic-compounds-l-4_5-yo2axycxrsy-038-1270.8.jpg"></p>
</div>
</main>
<hr>
<footer style="font-size:18px;"> Stereochemistry $\rightarrow$ Nitrogen chirality center $\rightarrow$ Ambident nucleophile $\rightarrow$ Reaction $\rightarrow$ <span style="color:blue">Discovery of sulfanilamide</span> $\rightarrow$ Proto alkaloids $\rightarrow$ Classification of alkaloids $\rightarrow$ Nicotine $\rightarrow$ Arecoline $\rightarrow$ Lobeline $\rightarrow$ The hofmann elimination $\rightarrow$ Regioselectivity in the hofmann elimination $\rightarrow$ The cope elimination $\rightarrow$ Reaction </footer>

<p><Success style="float:center;text-align:center;font-size:28px;"> <B>Nitrogen containing organic compounds Lecture-4</B></Success></p>
<p><primary style="float:center;text-align:center;font-size:24px;"> <B>The hofmann elimination</B></primary></p>
<hr>
<main>
<div style='float: left; width:60%;font-size:22px;text-align:left'>
<ul>
<li>
<p>In the late 19th century, the prominent German-born chemist, August W. von Hofmann (1818-1895), discovered that quaternary ammonium hydroxides on heating undergo an elimination reaction to produce an alkene</p>
</li>
<li>
<p>Hofmann made many important contributions to organic chemistry as a professor at the Royal College of Chemistry in London</p>
</li>
<li>
<p>In the traditional Hofmann elimination a primary amine with a $\beta$-H is exhaustively methylated to give a trimethylalkylammonium salt</p>
</li>
</ul>
</div>
<div style='float: right; width:40%;'>
<img src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/44fe7b2a-d7ac-40fe-bba7-6eb0baa45200/public" width="90%">
</div>
<div style='float: right; width:0%;'>
<p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-13-chapter-04-nitrogen-containing-organic-compounds-l-4_5-yo2axycxrsy-052-1648.8.jpg"></p>
</div>
</main>
<hr>
<footer style="font-size:18px;"> Stereochemistry $\rightarrow$ Nitrogen chirality center $\rightarrow$ Ambident nucleophile $\rightarrow$ Reaction $\rightarrow$ Discovery of sulfanilamide $\rightarrow$ Proto alkaloids $\rightarrow$ Classification of alkaloids $\rightarrow$ Nicotine $\rightarrow$ Arecoline $\rightarrow$ Lobeline $\rightarrow$ <span style="color:blue">The hofmann elimination</span> $\rightarrow$ Regioselectivity in the hofmann elimination $\rightarrow$ The cope elimination $\rightarrow$ Reaction </footer>

<p><Success style="float:center;text-align:center;font-size:28px;"> <B>Nitrogen containing organic compounds Lecture-4</B></Success></p>
<p><primary style="float:center;text-align:center;font-size:24px;"> <B>The hofmann elimination</B></primary></p>
<hr>
<main>
<div style='float: left; width:60%;font-size:22px;text-align:left'>
<ul>
<li>
<p><strong>Hofmann Elimination, An E2 Reaction</strong></p>
</li>
<li>
<p>The $4^0$ ammonium hydroxide is stable and may be isolated and purified. When it is heated in the solid state or in solution to around $200^{\circ} \mathrm{C}$ and $\mathrm{E} 2$ reaction occurs</p>
</li>
<li>
<p>The availability of a $\beta$-H is, of course, a requirement for this reaction</p>
</li>
</ul>
</div>
<div style='float: right; width:40%;'>
<img src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/93ead434-b4e6-4293-c259-786a429e5000/public" width="100%">
</div>
<div style='float: right; width:0%;'>
<p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-13-chapter-04-nitrogen-containing-organic-compounds-l-4_5-yo2axycxrsy-058-1836.0.jpg"></p>
</div>
</main>
<hr>
<footer style="font-size:18px;"> Stereochemistry $\rightarrow$ Nitrogen chirality center $\rightarrow$ Ambident nucleophile $\rightarrow$ Reaction $\rightarrow$ Discovery of sulfanilamide $\rightarrow$ Proto alkaloids $\rightarrow$ Classification of alkaloids $\rightarrow$ Nicotine $\rightarrow$ Arecoline $\rightarrow$ Lobeline $\rightarrow$ <span style="color:blue">The hofmann elimination</span> $\rightarrow$ Regioselectivity in the hofmann elimination $\rightarrow$ The cope elimination $\rightarrow$ Reaction </footer>

<p><Success style="float:center;text-align:center;font-size:28px;"> <B>Nitrogen containing organic compounds Lecture-4</B></Success></p>
<p><primary style="float:center;text-align:center;font-size:24px;"> <B>Regioselectivity in the hofmann elimination</B></primary></p>
<hr>
<main>
<div style='float: left; width:60%;font-size:22px;text-align:left'>
<ul>
<li>
<p>In quaternary ammonium hydroxides that have two or more nonequivalent $\beta$-H’s</p>
</li>
<li>
<p>The major product results from <span style="color:blue">abstraction of
the more or most acidic-$\beta H$.</span>
<span style="color:green">This is what is called the Hofmann rule</span></p>
</li>
<li>
<p>Since alkyl groups are electron-donating relative to $\mathrm{H}$, a $ \beta-\mathrm{H}$ is more acidic the fewer alkyl substituent are on the carbon to which it is attached</p>
</li>
</ul>
</div>
<div style='float: right; width:40%;'>
<img src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/6b96a43e-97ba-431f-5d49-07ccfa280000/public" width="90%">
</div>
<div style='float: right; width:0%; '>
<p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-13-chapter-04-nitrogen-containing-organic-compounds-l-4_5-yo2axycxrsy-060-1946.4.jpg"></p>
</div>
</main>
<hr>
<footer style="font-size:18px;"> Stereochemistry $\rightarrow$ Nitrogen chirality center $\rightarrow$ Ambident nucleophile $\rightarrow$ Reaction $\rightarrow$ Discovery of sulfanilamide $\rightarrow$ Proto alkaloids $\rightarrow$ Classification of alkaloids $\rightarrow$ Nicotine $\rightarrow$ Arecoline $\rightarrow$ Lobeline $\rightarrow$ The hofmann elimination $\rightarrow$ <span style="color:blue">Regioselectivity in the hofmann elimination</span> $\rightarrow$ The cope elimination $\rightarrow$ Reaction </footer>

<p><Success style="float:center;text-align:center;font-size:28px;"> <B>Nitrogen containing organic compounds Lecture-4</B></Success></p>
<p><primary style="float:center;text-align:center;font-size:24px;"> <B>The cope elimination</B></primary></p>
<hr>
<main>
<div style='float: left; width:60%;font-size:22px;text-align:left'>
<ul>
<li>
<p>Essentially a variation of the Hofmann elimination, the Cope starts with a $3^0$ amine oxide, another type of compound that has a positive charge on a fully substituted nitrogen just as the $4^0$ ammonium hydroxides that undergo Hofmann elimination do</p>
</li>
<li>
<p>The Cope is a syn elimination that proceeds through a cyclic transition state</p>
</li>
</ul>
</div>
<div style='float: right; width:40%;'>
<img src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/f8d2d02b-9d6b-4fa3-bf15-aa71c2ed4b00/public" width="90%">
</div>
<div style='float: right; width:00%;'>
<p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-13-chapter-04-nitrogen-containing-organic-compounds-l-4_5-yo2axycxrsy-067-2174.4.jpg"></p>
</div>
</main>
<hr>
<footer style="font-size:18px;"> Stereochemistry $\rightarrow$ Nitrogen chirality center $\rightarrow$ Ambident nucleophile $\rightarrow$ Reaction $\rightarrow$ Discovery of sulfanilamide $\rightarrow$ Proto alkaloids $\rightarrow$ Classification of alkaloids $\rightarrow$ Nicotine $\rightarrow$ Arecoline $\rightarrow$ Lobeline $\rightarrow$ The hofmann elimination $\rightarrow$ Regioselectivity in the hofmann elimination $\rightarrow$ <span style="color:blue">The cope elimination</span> $\rightarrow$ Reaction </footer>

<p><Success style="float:center;text-align:center;font-size:28px;"> <B>Nitrogen containing organic compounds Lecture-4</B></Success></p>
<p><primary style="float:center;text-align:center;font-size:24px;"> <B>The cope elimination</B></primary></p>
<hr>
<main>
<div style='float: left; width:100%;font-size:22px;text-align:left'>
<p><strong>An Example</strong></p>
<ul>
<li>Cyclohexylmethyl dimethylamine oxide $\underset{160^0}{\longrightarrow}$ Methylenecyclohexane $+ (CH_3)_2 NOH $</li>
</ul>
<p>98%</p>
</div>
<div style='float: right; width:0%;'>
<p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-13-chapter-04-nitrogen-containing-organic-compounds-l-4_5-yo2axycxrsy-067-2174.4.jpg"></p>
</div>
</main>
<hr>
<footer style="font-size:18px;"> Stereochemistry $\rightarrow$ Nitrogen chirality center $\rightarrow$ Ambident nucleophile $\rightarrow$ Reaction $\rightarrow$ Discovery of sulfanilamide $\rightarrow$ Proto alkaloids $\rightarrow$ Classification of alkaloids $\rightarrow$ Nicotine $\rightarrow$ Arecoline $\rightarrow$ Lobeline $\rightarrow$ The hofmann elimination $\rightarrow$ Regioselectivity in the hofmann elimination $\rightarrow$ <span style="color:blue">The cope elimination</span> $\rightarrow$ Reaction </footer>