Isomerism in complexes with the decahydro-closo-decaborate anion

The decahydro-closo-decaborate anion [B10H10](2-) and its reactivity in complexation reactions has been discussed. The recently obtained data on structure of neutral mixed-ligand metal(I) complexes of general formula [M-2[B10H10]L-x] have been generalized. A number of positional isomers with various positions of two metal(I) atoms around the bulky boron cluster and their structural features have been discussed. This approach has been extended to the substituted derivatives of the closo-decaborate anion with two substituents [B10H8X2](2-). The geometry of [B10H10](2-), namely the presence of apical and equatorial boron vertices, and the possibility to control the reaction provide a number of opportunities for design of various structures based on the 10-vertex boron cage. Positional isomers of complexes with dimeric 20-vertex clusters, iso- and trans-[B20H18](2-) anions, was also reported. In addition, some examples of classical isomers (conformational, geometrical, and hydrated) with outer-sphere [B10H10](2-) have been discussed. (C) 2015 Elsevier Ltd. All rights reserved.