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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 |

REPOSITORIES: biostudies-literature

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