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Stereoselective synthesis of tetrasubstituted alkenes via a sequential carbocupration and a new sulfur-lithium exchange.

ABSTRACT: We have designed a new sequential carbocupration and sulfur-lithium exchange that leads stereo- and regioselectively to trisubstituted alkenyllithiums. Subsequent trapping with various electrophiles yields tetrasubstituted olefins with good control of the double-bond geometry (E/Z ratio up to 99:1). The novel sulfur-lithium exchange could be extended to the stereoselective preparation of Z-styryl lithium derivatives with almost complete retention of the double-bond geometry.

SUBMITTER: Unsinn A

PROVIDER: S-EPMC3556915 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Stereoselective synthesis of tetrasubstituted alkenes via a sequential carbocupration and a new sulfur-lithium exchange.

Unsinn Andreas A Dunst Cora C Knochel Paul P

Beilstein journal of organic chemistry 20121218

We have designed a new sequential carbocupration and sulfur-lithium exchange that leads stereo- and regioselectively to trisubstituted alkenyllithiums. Subsequent trapping with various electrophiles yields tetrasubstituted olefins with good control of the double-bond geometry (E/Z ratio up to 99:1). The novel sulfur-lithium exchange could be extended to the stereoselective preparation of Z-styryl lithium derivatives with almost complete retention of the double-bond geometry. ...[more]

PMID: 23365630

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