Synthesis and photochemistry of ring-coupled heterobimetallic compounds of ruthenium.: The molecular structures of RuM(CO)5(μ-η5,η5-C5H4CR2C5H4), where M = Mo, R = CH3;: M = W, R = H, [Ru(CO)2][Mo(CO)3Cl](μ-η5,η1:η5-C5H4CH2C5H3) and [W(CO)3][Ru(CO)2Cl](μ-η5,η1:η5-C5H4CH2C5H3)

Reaction of the versatile reagent Ru(CO)(2)(mu-eta(5), eta(1)-C5H4CR2C5H4), where R = H or CH3, with M(CO)(6) or M(CO)(3)(CH3CN)(3), where M = Mo or W, yields bimetallic compounds of the form RuM(CO)(5)(mu-eta(5),eta(5)-C5H4CR2C5H4) in excellent yield, while reaction with Fe(CO)(5) yields RuFe(CO)(2)(mu-CO)(2)[mu-eta(5), eta(5)-C5H4C(CH3)(2)C5H4] in excellent yield. Reaction with Ni(CO)(4) yields thermally unstable RuNi(CO)(3)[mu-eta(5), eta(5)-C5H4C(CH3)(2)C5H4]. These compounds have been characterized by IR and NMR spectroscopies, and, with the exception of the Ru/Ni compound, elemental analysis. Photolysis of RuMo(CO)(5)[mu-eta(5), eta(5)-C5H4C(CH3)(2)C5H4] in the presence of triphenylphosphine yields both of the simple mono-carbonyl substitution products with the phosphine on Ru and Mo. Photolysis of the derivative with phosphine bound to the molybdenum yields [Ru(sigma-C6H5)(CO)][Mo(CO)(2)][mu-P(C6H5)(2)](mu-eta(5), eta(5)-C5H4C(CH3)(2)C5H4)[Ru- Mo]. Photolysis of RuFe(CO)(2)(mu-CO)(2)[mu-eta(5), eta(5)-C5H4C(CH3)(2)C5H4] with triphenylphosphine yields [Ru(CO)]{Fe[P(C6H5)(3)]}(mu-CO)(2)[mu-eta(5), eta(5)-C5H4C(CH3)(2)C5H4][Ru-Fe]. Photolysis of the Ru/Mo and Ru/W heterobimetallic compounds in deuterobenzene established that two metal-hydride species were formed, one whose chemical shift was characteristic of a CpRu(CO)(2)H and the second typical of a CpM(CO)(3)H. Photolysis of the Ru/Mo and Ru/W compounds in 20% chloroform in benzene followed by chromatography of the reaction mixtures permitted isolation of the isomeric photoproducts as their chloride derivatives. IR and NMR spectroscopy and X-ray crystallography of these compounds established them to have 'twist' structures in which one cyclopentadienyl ring is eta(1) to one of the metals and eta(5) to the second. The molecular structures of four compounds were determined: RuMo(CO)(5)[mu-eta(5), eta(5)-C5H4C(CH3)(2)C5H4]: monoclinic, P2(1)/n, a = 9.608(3), b = 12.613(4), c = 14.367(5) Angstrom, beta = 97.59(2)degrees, V = 1738.0(9) Angstrom(3), z = 4, R-F = 3.53. RuW(CO)(5)(mu-eta(5), eta(5)-C5H4CH2C5H4): monoclinic, P2(1)/c, a = 14.232(5), b = 7.833(3), c = 13.771(5) Angstrom, beta = 93.22(3)degrees, V = 1533(1) Angstrom(3), z = 4, R-F = 3.88. [Mo(CO)(3)][Ru(CO)(2)Cl](mu-eta(5), eta(1): eta(5)-C5H4CH2C5H3): monoclinic, P2(1)/c, a = 10.259(9), b = 12.666(5), c = 13.451(5(5) Angstrom, beta = 109.85(4)degrees, V = 1641(1) Angstrom(3), z = 4, R-F = 2.72. [Ru(CO)(2)][W(CO)(3)Cl](mu-eta(5), eta(1):eta(5)-C5H4CH2C5H3): monoclinic, P2(1)/c, a = 12.793(3), b = 9.485(2), c = 13.450(2) Angstrom, beta = 94.56(1)degrees, V = 1626.8(6) Angstrom(3), Z = 4, R-F = 3.67. (C) 2000 Elsevier Science S.A. All rights reserved.