Unusual migration of manganese to an arene via protonation of an agostic η3:CH-cyclohexenyl complex
Abstract
Treatment of the agostic compound [Mn(η3:CH-C6H8Ph)(CO)3]1a with HBF4·Et2O in CH2Cl2 gave the arene complex [Mn{η6-C6H5(C6H9)}(CO)3][BF4]2via migration of the metal from the cyclohexenyl ring to the aryl substituent. Reaction of 2 with the nucleophiles triphenylphosphine and methylmagnesium chloride respectively gave the substitution product [Mn{η6-C6H5(C6H9)}(CO)2(PPh3)][BF4]3 and the addition product [Mn{η5-C6H5Me(C6H9)}(CO)3]4 as a mixture of isomers. The crystal structure of complex 2 has been determined: triclinic, space group P, a= 9.399(3), b= 10.644(2), c= 8.979(1)Å, α= 93.03(1), β= 116.39(2), γ= 79.45(3)°, R= 0.057 for 1316 independent reflections.