Proposal for the metallacycle pathway during the cyclopropanation catalyzed by cobalt-Schiff base complexes.
[reaction: see text] The density functional study of the cobalt(II) complex-catalyzed cyclopropanation revealed that the cobalt(II)-Schiff base complex without an ethylene bridge would be flexible enough to transform into the cis-beta conformer while approaching the olefin; consequently, the metallacycle pathway would be preferred, while the ethylene bridge would stabilize the planar conformer to allow reaction via the concerted mechanism.
Iwakura
Izumi
I
Department of Chemistry, Faculty of Science and Technology, Keio University, Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan.
Ikeno
Taketo
T
Yamada
Tohru
T