Regiospecific functionalization of cyclic allenes with catecholeorane

Abstract

Reaction of diborane and disiamylborane with cyclic allenes, resulted in the formation of a mixture of products resulting from the addition of boron at the central carbon as well as terminal carbon. Fish has reported that addition of 4, 4, 6-trimethyl-1, 3, 2-dioxaborinane to 1, 3-disubstituted allenes takes place at the central carbon atom preferentially when the hydroboration was done at 130° for 35-50 h in a sealed tube. The reactivity and stability of catecholborane at high temperatures which is known to provide greater stearic.