Syntheses and structures of two trifluoroacetate-trapped derivatives of a ruthenium butatrienylidene complex

The alkynyl ketone [Ru(C[equivalent to]CCOCHMe[sub 2])-(PPh[sub 3])[sub 2](Cp)] (1) reacts with trifluoroacetic anhydride at ambient temperature to give [Ru(C[equivalent to]CC(OCOCF[sub 3])CMe[sub 2])(PPh[sub 3])[sub 2](Cp)][center dot]0.5Et[sub 2]O (2), an enynyl trifluoracetate ester which structurally resembles a ruthenium butatrienylidene cation ([Ru=C=C=C=CR[sub 2]][sup +]) trapped by the attachment of a trifluoroacetate anion to C[gamma]. Compound 1 also reacts with 2 equiv of trifluoroacetic anhydride to form [Ru(C=C(COCF[sub 3])C(OCOCF[sub 3])-CMe[sub 2])(PPh[sub 3])[sub 2](Cp)][H(CF[sub 3]CO[sub 2])[sub 2]] (3), in which C[sub beta] of compound 2 has been acylated by a trifluoroacetyl group. The structures of 2 and 3 have been determined by X-ray crystallography. 16 refs., 1 fig.