Conversion of the allenyl complexes (PPh3)(2)Pt(mu-eta(1):eta(2)(alpha,beta)-C(R)=C=CH2)Ru(CO)Cp to the hydrido-alkylidene complexes (PPh3)(2)Pt(mu-H)(mu-eta(1):eta(1)-C(R)C(O)CH3)Ru(CO)Cp (R = H, Ph) by reaction with water under heterogeneous conditions

Treatment of (PPh3)(2)Pt((mu-eta(1):eta(alpha,beta)(2)-C(R)=C=CH2)Ru(CO)Cp (R = H (1), Ph (2)) in CH2Cl2 or CHCl3 solution with deactivated alumina, s ilica or Florisil affords the corresponding hydridoalkylidene complexes (PP h3)(2)Pt(mu-H)(mu-eta(1):eta(1)-C(R)C(O)CH3)Ru(CO)Cp (R = H (3), Ph (4)) in less than or approximately 50% yield. The conversion of I to 3 is promoted by use of acidic alumina. There is no reaction in the oxygenated solvents THF or diethyl ether, or in CHCl3-H2O without the added solid support. Acti vated alumina suppresses this 'hydration' reaction, as does added free radi cal inhibitor nitrosobenzene or benzoquinone, all in CH2Cl2 or CHCl3. Compl exes 3 and 4 were characterized by IR and H-1, C-13{H-1} and P-31{H-1} NMR spectroscopy and elemental analysis, and the structure of 3 was determined by single crystal X-ray diffraction analysis. (C) 2000 Elsevier Science S.A . All rights reserved.