title: Synthesis of heterometal cluster complexes by the reaction of cobaltadichalcogenolato complexes with groups 6 and 8 metal carbonyls.
abstract: Metalladichalcogenolate cluster complexes [{CpCo(S2C6H4)}2Mo(CO)2] (Cp = eta(5)-C5H5) (3), [{CpCo(S2C6H4)}2W(CO)2] (4), [CpCo(S2C6H4)Fe(CO)3] (5), [CpCo(S2C6H4)Ru(CO)2(P(t)Bu3)] (6), [{CpCo(Se2C6H4)}2Mo(CO)2] (7), and [{CpCo(Se2C6H4)}(Se2C6H4)W(CO)2] (8) were synthesized by the reaction of [CpCo(E2C6H4)] (E = S, Se) with [M(CO)3(py)3] (M = Mo, W), [Fe(CO)5], or [Ru(CO)3(P(t)Bu3)2], and their crystal structures and physical properties were investigated. In the series of trinuclear group 6 metal-Co complexes, 3, 4, and 7 have similar structures, but the W-Se complex, 8, eliminates one cobalt atom and one cyclopentadienyl group from the sulfur analogue, 4, and does not satisfy the 18-electron rule. 1H NMR observation suggested that the CoW dinuclear complex 8 was generated via a trinuclear Co2W complex, with a structure comparable to 7. The trinuclear cluster complexes, 3, 4, and 7, undergo quasi-reversible two-step one-electron reduction, indicating the formation of mixed-valence complexes Co(III)M(0)Co(II) (M = Mo, W). The thermodynamic stability of the mixed-valence state increases in the order 4 < 3 < 7. In the dinuclear group 8 metal-Co complexes, 5 and 6, the CpCo(S2C6H4) moiety and the metal carbonyl moiety act as a Lewis acid character and a base character, respectively, as determined by their spectrochemical and redox properties. Complex 5 undergoes reversible two-step one-electron reduction, and an electron paramagnetic resonance (EPR) study indicates the stepwise reduction process from Co(III)Fe(0) to form Co(III)Fe(-I) and Co(II)Fe(-I).
authors.affiliation: Department of Chemistry, School of Science, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Murata
authors.forename: Satoru
authors.initials: S
authors.lastname: Habe
authors.forename: Shingo
authors.initials: S
authors.lastname: Araki
authors.forename: Kosuke
authors.initials: K
authors.lastname: Namiki
authors.forename: Teppei
authors.initials: T
authors.lastname: Yamada
authors.forename: Norikiyo
authors.initials: N
authors.lastname: Nakagawa
authors.forename: Takuya
authors.initials: T
authors.lastname: Nankawa
authors.forename: Masayuki
authors.initials: M
authors.lastname: Nihei
authors.forename: Jun
authors.initials: J
authors.lastname: Mizutani
authors.forename: Masato
authors.initials: M
authors.lastname: Kurihara
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nishihara