Preparation of 1-p-halophenyl and 1-p-biphenylyl substituted monocarbadodecaborate anions [closo-1-Ar-CB11H11]- by insertion of arylhalocarbenes into [nido-B11H14]-

In the presence of a strong base, benzal chloride (C(6)H(5)CHCl(2)) and its p-substituted derivatives react with nido-B(11)H(14)](-) to yield closo-1-p-X-C(6)H(4)-CB(11)H(11)](-) (X = H, F, Cl, Br, I, Ph), presumably by insertion of an arylhalocarbene and oxidation. On a 1-g scale, the yields are 30-40%, except in the case of p-iodobenzal chloride, which yields only 12% of the insertion product.