INSERTION REACTIONS OF ACETYLENES WITH HYDRIDOCARBONYL-CHLOROTRIS(TRIPHENYLPHOSPHINE)RUTHENIUM(II). X-RAY STRUCTURE OF CARBONYLCHLORO(cis-1,2-DIPHENYLETHENYL)BIS(TRIPHENYLPHOSPHINE)RUTHENIUM(II)

Article abstract of DOI:10.1016/S0022-328X(00)99582-2

Reactions between Ru(CO)ClH(PPh3)3 and phenylacetylene, pent-1-yne and diphenylacetylene in CH2Cl2 give the red crystalline alkenyl species Ru(CO)Cl(RC=HR')(PPh3)2 (R = H, R'= C3H7, Ph; R = R' = Ph), which can be regarded as resulting from elimination of one phosphine molecule and insertion of the alkyne into the Ru-H bond.The reaction with phenylacetylene in MeOH/CH2Cl2 (1/1) gives the yellow crystalline complex Ru(CO)Cl(PhC=CH2)-(PPh3)3, seemingly resulting from a simple insertion of the alkyne into the Ru-H bond.The complexes have been characterized by elemental analysis and 1H NMR and IR spectroscopy.The molecular structure of Ru(CO)Cl(PhC=CHPh)(PPh3)2, determined by X-ray diffraction, can be described as a distorted trigonal bipyramidal species, in which the phosphine molecules occupy the axial positions and the alkenyl ligand has the phenyl groups in a cis configuration.Similar molecular structures are probable for the other red complexes.The yellow complex derived from phenylacetylene seems to be a six-coordinate species, in which two phosphine molecules are respectively cis- and trans-coordinated with respect to the alkenyl ligand.