Pure and Applied Chemistry

Abstract: The controlled synthesis of carborane anions is a difficult challenge and is of great interest to synthetic chemists. By varying the bridge length of cage carbons-linked o-carboranes, the two cage carbon atoms are locked in place during the reactions, leading to the controlled synthesis of ortho-, meta- and para-isomer of nido-carborane dianions. The isomers of arachno-carborane tetraanions can also be prepared in the controlled manner via chang- ing the electronic configuration of the transition-metal ions or the bridge length. This article provides an overview of our recent work on this subject.