Synthesis and characterisation of the exo-nido molybdacarborane complex Mo(η-C3H5)(CO)2(7,8-μ-SCH2CH2S-7,8-nido-C2B9H10). Strong BHMo 3-centre bonding
作者:Gemma Barberà、Clara Viñas、Francesc Teixidor、Georgina M Rosair、Alan J Welch
DOI:10.1016/s0022-328x(02)01736-9
日期:2002.12
Reaction of [7,8-mu-SCH2CH2S-7,8-nido-C2B9H10] - and MoBr(eta-C3H5)(CO)(2)(MeCN)(2) in THF affords the zwitterionic exo-nido molybdacarborane complex MO(eta-C3H5)(CO)(2)(7,8-mu-SCH2CH2S-7,8-nido-C2B9H10), characterised by(1)H- and B-11-NMR spectroscopy and by a crystallographic study. The complex is fluxional (having mirror symmetry on the NMR timescale) in solution at room temperature although asymmetric in the solid state. Data are presented which suggest a significant 3c-2e B3-H3-Mo bond. Deprotonation of [7,8-mu-SCH2CH2S-7,8-nido-C2B9H10]- with (LiNPr2)-Pr-i followed by reaction with MoBr(eta-C3H5)(CO)(2)(MeCN)(2) affords Li[1,2-mu-SCH2CH2S-3-(eta-C3H5)-3,3-(CO)(2)-3,1,2-closo-MoC2B9H9] for which H-1- and B-11-NMR data are reported. (C) 2002 Elsevier Science B.V. All rights reserved.