(5)-METHYLCYCLOPENTADIENYL)DIHYDRIDOMOLYBDENUM(IV) - SYNTHESIS AND REACTIONS WITH NUCLEOPHILES IN THE PRESENCE OF PROTONIC ACIDS

[Mo(eta5-MeCp)2H2] (3) (MeCp=C5H4Me) which was prepared by the reactio n of MoCl5 with Na(MeCp) in the presence of NaBH4 was treated with p-t oluenesulfonic acid (TsOH) to give [Mo(eta5-MeCP)2H(OTs)]. Reactions o f 3 with allyl alcohol in the presence of TsOH yielded (Mo(eta5-MeCP)2 (eta3-C3H5)]+TsO- whereas the similar reaction with 2-methyl-2-propen- 1-ol yielded [Mo(MeCp)2CH2CH(Me)CH2OH]+TsO-. When the reactions of 3 w ith protonic acid HA (HA=TsOH and AcOH) were carried out in the presen ce of acetone or 4-t-butykyclohexanone, [Mo(eta5-MeCP)2A2] were formed accompanied by the reduction of ketones to the corresponding alcohols . The results are compared with the similar reactions with cyclopentad ienyl analog of 3.