名称:
Metallacarborane chemistry of the hypho-[6,7-C2B6H13]− anion: the formation of uniquely structured metallacarboranes [5-Cp∗-arachno-5,4,6-RhC2B6H12]and[2,5-Cp2∗-10-Me-nido-2,5,1-Rh2CB6H9](Cp∗=η5-C5Me5-): complete rhodium analogues of arachno-4,6-C2B7H13 and nido-1-CB8H12
摘要:
Reaction of the tetramethyl ammonium salt of the hypho-[6,7-C2B6H13](-) anion (1) with the [Rh(eta(5)-C5Me5)Cl-2](2) dimer in THF solution, resulted in the formation of a novel nine-vertex metalladicarbaborane [5-Cp*-arachno-5,4,6-RhC2B6H12](2) (Cp* = eta(5)-C5Me5). An analogous reaction, but in the presence of PS (PS='proton-sponge'=1,8-bis-(dimethylamino)-naphthalene), resulted in the bimetallic nine-vertex species [2,5-Cp*(2)-10-Me-nido-2,5,1-Rh2CB6H9] (3). Compounds 2 and 3 are structural analogues of carboranes arachno-4,6-C2B7H13 (4) and nido-1-CB8H12 (5), respectively. The formation of compound 3 is associated with an extrusion of one of the cluster carbon atoms into an exo-polyhedral position and exhibits a very rare nine-vertex nido metallaborane structure with interesting features. Both species 2 and 3 were characterized by multinuclear NMR measurements and single-crystal X-ray diffraction studies. (C) 2004 Elsevier B.V. All rights reserved.