Probable C-H activation of acetone under mild conditions by a neutral Pt(II) compound and the formation of the acetonyl complex [Pt(CH2COCH3)Cl(bipy)] (bipy = 2,2'-bipyridyl) (1) are reported. The complex [Pt(CH2COCH3)Cl(bipy)] has been characterized by IR and H-1 NMR spectroscopy, elemental (C, N and H) analysis and X-ray diffraction. Complex 1 crystallizes in the triclinic space group 
:a = 7.6599(9), b = 9.157(2), c = 9.306(1) Angstrom, alpha = 87.581(8)degrees, beta = 78.174(9)degrees, gamma = 79.59(1)degrees, Z = 2. The possible mechanism and some factors that influence the formation of this complex are discussed. (C) 1997 Elsevier Science S.A.