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Silver catalyzed proto- and sila-Nakamura-type ?-vinylation of silyl enol ethers with dichloroacetylene. Divergent formation of stereochemically pure tri- and tetrasubstituted olefins.

ABSTRACT: The silver-catalyzed reaction of silyl enol ethers with dichloroacetylene (DCA) is described. When DCA was used as a solution in diethyl ether, we found that the silyl group was transferred to the vinyl group, resulting in stereochemically pure tetrasubstituted olefins. However, when DCA was used as a solution in the more polar acetonitrile, protonation was the major pathway, and trisubstituted olefins were the dominant products.

SUBMITTER: Li L

PROVIDER: S-EPMC7450970 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Silver catalyzed proto- and sila-Nakamura-type α-vinylation of silyl enol ethers with dichloroacetylene. Divergent formation of stereochemically pure tri- and tetrasubstituted olefins.

Li Lun L Wasik Kimberly A KA Frost Brian J BJ Geary Laina M LM

Tetrahedron letters 20191106 2

The silver-catalyzed reaction of silyl enol ethers with dichloroacetylene (DCA) is described. When DCA was used as a solution in diethyl ether, we found that the silyl group was transferred to the vinyl group, resulting in stereochemically pure tetrasubstituted olefins. However, when DCA was used as a solution in the more polar acetonitrile, protonation was the major pathway, and trisubstituted olefins were the dominant products. ...[more]

PMID: 32863449

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