Preparation of cationic cyclopentadienyl diene molybdenum complexes through hydride abstraction effected by di- or triarylmethyl halides in the presence of hexafluoro-2-propanol

Hydride abstraction from the model system (eta (5)-cyclopentadienyl)dicarbo nyl[(1-3-eta)-1-cyclohexen-3-yl] molybdenum (1) was effected using halides such as Ph3CCl (3b), Ph3CBr (3a), and (4-MeOC6H4)(2)CHBr (5), or their poly mer-bound analogues, as carbocation precursors. The presence of hexafluoro- 2-propanol (HRP) as a cosolvent was critical for hydride abstraction to pro ceed. Good yields of (eta (5)-cyclopentadienyl)dicarbonyl [(1 -4-eta)-cyclo hexadiene] molybdenum halides 2a,b were obtained from soluble as well as po lymer-supported hydride abstractors. The influence of HRP concentration and carbocation precursor on reaction efficiency was investigated.