Evidence for Synclinal Transition State in the Reactions of Aromatic Aldehydes with α-(Alkoxy)allylstannanes
摘要:
Unlike aliphatic aldehydes, aromatic aldehydes produce greater than 95% of syn-(Z) enol ether when treated with alpha-(alkoxy)allylstannanes in the presence of BF3.Et2O. However, in the presence of TiCl4, the reaction of p-chloro-o-methoxybenzaldehyde with alpha-(alkoxy)crotylstannane produced predominantly the syn-(E) isomer.