| Abstract
| - [Mo(η2-CS3)4]3- (1) and [Mo2(μ2-S2)2(η2-CS3)2]2- (2) were obtained by the activation of CS2 by MoS42- in methanol. A pathway is given to explain the formation of 1 and 2.
- This paper describes the syntheses and structures of two new Mo(V) compounds obtained via the reductive additionof CS2 on the high-valent tetrathiometalate MoS42-. The mononuclear compound (NEt4)3[Mo(η2-CS3)4], 1, wasselectively produced by reaction of (NEt4)2[MoS4] with excess of CS2 in a mixture of CH3OH and NH3 in thepresence of H2S. Compound 1 crystallizes in the monoclinic system, space group P21/n, a = 18.5249(5) Å, b =11.8058(4) Å, c = 20.2942(5) Å, β = 102.951(1)°, Z = 4. In total, 11 176 reflections with I> 2σ(I) wereemployed, and the structure solution was refined to R = 0.0496. Compound 1 was revealed to be a mononuclearparamagnetic species containing only η2-CS3 ligands. The geometry at the Mo(V) center is described as a regulardodecahedron. Compound 1 represents a unique example of a stable mononuclear Mo(V) complex containingtrithiocarbonate ligands. The reaction of [MoS4]2- with CS2 without H2S gives (NBu4)2[Mo2(η2-CS3)4(μ-(S2)2],2, obtained as a powder which was recrystallized at 4 °C. Compound 2 crystallizes in the monoclinic system,space group P21/n, a = 8.7930(1) Å, b = 22.3059(3) Å, c = 14.5029(2) Å, β = 98.445(1)°, Z = 4. In total, 8323reflections with I> 2σ(I) were used, and the structure solution was refined to conventional R = 0.0425. Compound2 is a dinuclear species containing η2-CS3 ligands, the two Mo(V) being linked through two disulfido bridginggroups. The Mo−Mo distance in 2 is 2.8128(6) Å, a value in very good agreement with those observed fordinuclear Mo(V) species.
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