Tert-Butyldimethylsilyldihalomethyllithium as a dihalomethylene dianion synthon. 1,3-Rearrangement and 1,4-rearrangement of silyl group from carbon to oxide

Abstract

One-pot synthesis of R 1CH(OSiMe 2- t-Bu)CX 2CH(OH)R 2 (X=Cl, Br) successive addition of two different aldehydes (R 1CHO and R 2CHO) has been achieved starting from tert-butyldimethylsilyldihalomethyllithium. Treatment of a THF solution of the title carbanion (X=Cl) with p-MeOC 6H 4CHO or n-BuCHO followed by an addition of HMPA and benzaldehyde gave the corresponding 1,3-diol monosilyl ether in 83% or 45% yield, respectively. The use of oxirane in place of aldehyde as the first electrophile followed by addition of benzaldehyde provided 1,4-diol monosilyl ether.