THE INTERPLAY OF ALKYLIDYNE AND CARBABORANE LIGANDS AT METAL CENTERS .2. PROTON-MEDIATED REACTIONS

This chapter covers protonation reactions of the alkylidyne(carbaborane) complexes of the group 6 metals that are depicted in structural formulae. Many of the reactions described were carried out in the presence of donor substrate molecules, resulting in the observation of new B–C, P–C, C–C, and metal–metal bond-forming processes. Novel low temperature polytopal rearrangements, cage degradation reactions, and metal-cage interactions have been discovered, as a consequence of the formation of molecules with unusual structures. The complexes explained in this chapter demonstrate the ways in which the proton, the simplest of all chemical reagents, can be used to unlock the potential of alkylidyne(carbaborane) metal complexes. Most metallacarbaborane complexes so far reported have generally displayed reactivity patterns involving the carbaborane cage, rather than the ligands attached to the metal vertices, the metal-bound exopolyhedral ligands usually remaining inert. © 1993, Academic Press Inc. All rights reserved.