Reaction of an optically active (1-methyl-2,2-diphenylcyclopropyl)trimethyltin (I) with bromine (or iodine) afforded 1-bromo-(or iodo)-1-methyl-2,2-diphenylcyclopropane (II) with a small degree of retention of configuration. This is best interpreted in terms of radical mechanism for the cleavage of the cyclopropyl carbontin bond in (I) by bromine or iodine.
Mechanism of grignard reagent formation. Further evidence for the surface nature of the reaction
作者:Janusz Rachon、H.M. Walborsky
DOI:10.1016/s0040-4039(00)70693-9
日期:1989.1
The use of Rieke magnesium permits one to obtain reaction with (S)-(+)-1-bromo-1-methyl-2,2-diphenylcyclopropane (1) at −65°C to yield a chiral Grignard reagent that is 33–43% optically pure.