Competition between intra- and inter-molecular reactions of borates: a new route to 1,4-dihydro-1,4-distannines

Abstract

The reaction of the system (E)-2-dimethyl(chloro)stannyl-3-diethylborylpent-2-ene (1)–LiNEt₂ in hexane can be controlled to give 1,4-dihydro-1,1,2,4,4,5-hexamethyl-3,6-diethyl-1,4-distannine (3) in high yield, demonstrating the intermediacy of aminoborate (5) and the preference (under the reaction conditions) of intermolecular electrophilic attack at the B–C bond accompanied by final elimination of LiCl and Et₂NBEt₂(4).