Polymethylated and Poly(tert)butylated Diphenylcarbenes. Generation, Reactions, Kinetics, and Deuterium Isotope Effects of Sterically Congested Triplet Carbenes

摘要

Dimesitylcarbene (2a) was shown to decay by undergoing dimerization and to have a half-life of 160 ms, some 5 orders of magnitude longer-lived than diphenylcarbene. Didurylcarbene (2b) was twice as long-lived as 2a, while decamethyldiphenylcarbene (2c) decayed mainly unimolecularly by abstracting H from the o-methyl group and became shorter-lived than 2b.