Molecular construction based on icosahedral carboranes and aromatic urea groups. A new type of carboracycle

Abstract Members of a new family of macrocyclic compounds incorporating icosahedral carboranes are described, together with their precursors. These macrocycles ( 1 – 3 ) are composed of 1,7-dicarba- closo -dodecaborane ( m -carborane) moieties linked via their carbon vertices through N , N ′-dimethyldiphenylurea groups. The structures of 1 – 3 have been determined by X-ray crystallography.