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Stereochemistry of the Kulinkovich cyclopropanation of nitriles.

ABSTRACT: The stereochemistry of the Kulinkovich cyclopropanation of nitriles with alkenes has been examined by employing (E)-disubstituted alkenes and deuterium-labeled homoallylic alcohols as a stereochemical probe. An intramolecular cyclopropanation proceeds with preservation of the olefin configuration. On the other hand, intermolecular counterparts occur with both preservation and reversal of the olefin configuration, which corresponds to retention and inversion of configuration at the Ti-C bond, respectively, in the cyclopropane-forming step. These uncommon stereochemical outcomes contrast with that of the Kulinkovich cyclopropanation of tertiary amides.

SUBMITTER: Astashko D

PROVIDER: S-EPMC2739442 | biostudies-literature | 2009 Aug

REPOSITORIES: biostudies-literature

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Stereochemistry of the Kulinkovich cyclopropanation of nitriles.

Astashko Dmitry D Lee Hyung Goo HG Bobrov Denis N DN Cha Jin K JK

The Journal of organic chemistry 20090801 15

The stereochemistry of the Kulinkovich cyclopropanation of nitriles with alkenes has been examined by employing (E)-disubstituted alkenes and deuterium-labeled homoallylic alcohols as a stereochemical probe. An intramolecular cyclopropanation proceeds with preservation of the olefin configuration. On the other hand, intermolecular counterparts occur with both preservation and reversal of the olefin configuration, which corresponds to retention and inversion of configuration at the Ti-C bond, res ...[more]

PMID: 19527011

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