Conversion of the allenyl complexes (PPh3)2Pt(μ-η1:η2α,β-C(R)CCH2)Ru(CO)Cp to the hydrido-alkylidene complexes (PPh3)2Pt(μ-H)(μ-η1:η1-C(R)C(O)CH3)Ru(CO)Cp (R=H, Ph) by reaction with water under heterogeneous conditions