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.
Subject(s)
Cyclopropanes/chemical synthesis , Nitriles/chemistry , Alkenes/chemistry , Cyclization , Cyclopropanes/chemistry , Molecular Structure , StereoisomerismABSTRACT
We report herein olefin exchange-mediated cyclopropanation of nitriles with homoallylic alcohols. The use of homoallylic alcohols is central to the successful implementation.
