The titanium tetrachloride-mediated alkynylation and allylation of a steroidal aldehyde via stannylacetylenes and allylstannanes with high cram selectivity
Abstract
The reaction of a steroidal aldehyde (1) with stannylacetylenes (2c) in the presence of TiCl4 produces the Cram isomer (3) with high diastereoselectivity.