{"id":1686,"date":"2018-11-29T21:38:49","date_gmt":"2018-11-29T21:38:49","guid":{"rendered":"https:\/\/courses.lumenlearning.com\/suny-potsdam-organicchemistry2\/?post_type=chapter&p=1686"},"modified":"2019-01-09T07:15:28","modified_gmt":"2019-01-09T07:15:28","slug":"21-2-general-mechanism","status":"publish","type":"chapter","link":"https:\/\/courses.lumenlearning.com\/suny-potsdam-organicchemistry2\/chapter\/21-2-general-mechanism\/","title":{"raw":"21.2 General mechanism","rendered":"21.2 General mechanism"},"content":{"raw":"
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General mechanism for addition of weak nucleophiles to carbonyls<\/h2>\r\n
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\r\n\r\nWeak nucleophiles are not strong enough to add to a simple C=O bond.\u00a0 They require the carbon to be made more electrophilic, and this can be done using either a Lewis acid or simply H+<\/sup>. We will focus on activation using simple acid - a process called protonation.\u00a0 This leads to an activated, charged form of the C=O which is now electrophilic enough to react with even weak nucleophiles via nucleophilic addition.\r\n\r\nMost often the weak nucleophiles are uncharged compounds such as alcohols (ROH) or amines (RNH2<\/sub> or similar).\u00a0 With these neutral nucleophiles, the product of the nucleophilic addition step is a positively charged compound, and so there is usually a final acid-base step to remove the unwanted H+<\/sup> (\"deprotonation\") and form the final uncharged product.\r\n\r\n<\/div>\r\n
\r\n\r\nMechanism<\/span>\r\n\r\n<\/div>\r\n
\r\n\r\n1)\u00a0 Protonation of the carbonyl\"\"\r\n\r\n2)\u00a0 Nucleophilic addition to the activated carbonyl\r\n\r\n\"\"\r\n\r\n3) Deprotonation\"\"\r\n\r\nContributors<\/span>\r\n\r\n<\/div>\r\n
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