摘要:
MgBr2 catalysed allylation of a series of diprotected asymmetrized bis (hydroxymethyl)acetaldehydes 2 with allyltributylstannane proceeds with good diastereoselectivity. The stereochemical results are in line with a cyclic chelated transition state, where only one of the two CH2OR appendages, due to the different nature of protecting groups, is capable of coordinating the Lewis acid.