The Reactions of Copper(I) 1-Alkenyltrimethylborates with Allylic Bromides or 2-Propynyl Bromide

The reactions between copper(I) 1-alkenyltrimethylborates (readily obtainable from 2-(1-alkenyl)-1,3,2-benzodioxaboroles and methyllithium) and allylic bromides or 2-propynyl bromide were found to give corresponding coupling products. These reactions provide new synthetic routes to 1,4-alkadienes or 1,2,7-alkatrien-5-ynes.