Synthesis, Crystal Structure, and Some Transformations of 9,12-Dichloro-ortho-Carborane

Abstract

Reaction of ortho-carborane with anhydrous AlCl3 in chloroform results in a mixture of 9-chloro, 9,12-dichloro, and 8,9,12-trichloro derivatives with 9,12-dichloro-ortho-carborane being the main product. Molecular crystal structure of 9,12-dichloro-ortho-carborane was determined by the single crystal X-ray diffraction. The crystal structure of 9,12-Cl2-1,2-C2B10H10 appeared to be nearly isostructural to 9,12-dibromo-ortho-carborane: the crystal packing is built of layers in which molecules are connected via weak hydrogen and halogen bonds. A synthetic scheme for preparation of the hexachloro derivative of cobalt bis(dicarbollide) Cs[8,8′,9,9′,12,12′-Cl6-3,3′-Co(1,2-C2B9H8)2] from 9,12-dichloro-ortho-carborane has been proposed.