(C5Me5)Ru-vinylidene complexes from terminal alkynes and propargyl alcohol derivatives

Complex (C(5)Me(5))(PMe(2)Ph)(2)RuCl (1) reacts with phenylacetylene and (trimethylsilyl)acetylene, in methanol with NH4PF6, to afford vinylidene complexes [(C(5)Me(5))(PMe(2)-Ph)(2)Ru=C=CHR]PF6 (R = Ph (3), H (5), respectively). Complexes 3 and 5 are stable toward the addition of alcohol due to the steric hindrance and electron-releasing capability of the (C(5)Me(5))(PMe(2)Ph)(2)Ru moiety as indicated by an oxidation potential of E(1/2) = 0.30 VSCE for 1. Complex 3 is slowly oxidized in the presence of air to give [(C(5)Me(5))(PMe(2)Ph)(2)RuCO]PF6 (4). The activation of HC=CCH2OH with 1 leads to the formation of the vinylidene moiety [Ru=C=CHCH2OH]PF6 (7) in dichloromethane and [Ru=C=CHCH(2)OMe]PF6 (6) in methanol, showing the lability of the hydroxy group without dehydration. The activation of HC drop CCH(OH)Me with 1 allows the formation of chiral vinylidene [(C,Mes)(PMe(2)-Ph)(2)Ru=C=CHCH(OMe)Me]PF6 (8). The vinylidenes 3, 6, and 8 are easily deprotonated to afford the corresponding alkynylruthenium complexes (C(5)Me(5))(PMe(2)Ph)(2)RuC drop CR' (R' = Ph (9), CH(2)OMe (10), CH(OMe)Me (11)). The molecular structures of [(C(5)Me(5))(PMe(2)-Ph)(2)Ru=C=CHPh)] [(C(5)Me(5))(PMe(2)Ph)(2)Ru(CO)](PF6)(2) (3.4) and [(C(5)Me(5))(PMe(2)Ph)(2)Ru=C=CHCH(Me)OMe]PF6 (8) were determined by X-ray crystallographic analysis. Complexes 3.4 crystallizes in the orthorhombic space group P2(1)2(1)2(1) With a 12.468(1) Angstrom, b = 14.282(2) Angstrom, c = 36.297(3) Angstrom, z = 4, R = 0.064, and R(w) = 0.0069. Complex 8 crystallizes in the orthorhombic space group Pbcn with a = 17.771(2) Angstrom, b = 19.277(3) Angstrom, c = 20.172(6) Angstrom, z = 8, R = 0.045, and R(w) = 0.043.