REACTIONS OF [RUH(ETA(3)-C3H5)(CO)(P(I)PR3)(2)] AND [RU(ETA(2)-C(2)PH(2))(CO)(P(I)PR3)(2)] WITH TERMINAL ALKYNES - SYNTHESIS AND CHARACTERIZATION OF NEW 5-COORDINATE AND 6-COORDINATE BIS(ALKYNYL) AND ALKYNYL(VINYL) DERIVATIVES OF RUTHENIUM(II)

The reaction of the complex [RuHCl(CO)((PPr3)-Pr-i)(2)] with C3H5MgBr affords [RuH(eta(3)-C3H5)(CO)((PPr3)-Pr-i)(2)] (2). This complex reacts with terminal alkynes. With CyC(2)H it yields [Ru(C(2)Cy)(2)(CO)((PPr3)-Pr-i)(2)] (3), whereas with Me(3)SiC(2)H it gives a mixture of [Ru(C(2)SiMe(3))(2)(CO)((PPr3)-Pr-i)(2)] (4) and [Ru(C(2)SiMe(3)) {(E)-CH=CHSiMe(3)}(CO)((PPr3)-Pr-i)(2)] (5). 4 was obtained as a spectroscopically pure oil by reaction of [RuH(eta(2)-H2BH2)(CO)((PPr3)-Pr-i)(2)] (15) with Me(3)SiC(2)H. 2 also reacts with PhC(2)Ph giving [Ru(eta(2)-C(2)Ph(2))(CO)((PPr3)-Pr-i)(2)] (6), which with RC(2)H then yields [Ru(C(2)R){(E)-CH=CHR}(CO)((PPr3)-Pr-i)(2)] (R = Cy (11), or -CO2CH3 (12)). Under CO, 3 and 4 give [Ru(C(2)R)(2)(CO)(2)((PPr3)-Pr-i)(2)](R = Cy (7) or (Me(3)Si (8)), but 5, 11 and 12 afford [Ru(C(2)R){(E)-CH=CHR}(CO)(2)((PPr3)-Pr-i)(2)] (R = Me(3)Si (9), Cy (13), or -CO2CH3 (14)). 15 catalyzes the cyclotrimerization of methyl propiolate to give a mixture of 1,3,5-C6H3(CO2CH3)(3) and 1,2,4-C6H3(CO2CH3)(3) in a 2:1 molar ratio.