The reaction of propargylic substrates with organocopper species can yield two major products, a substituted allene or a new acetylene. This paper is a study of the factors which influence the distribution of these products in this displacement (eg, 1-2+ 3). Those factors are (1) organocopper reagent stochiometry (R3CuLiz, RzCu-, RCu metal salt),(2) organocopper species concomitant salt or counterion (It@', Li'),(3) acetylenic site ...
