Synthesis and crystal structure of a new salt of the complex anion [(TCNQ) 3] 2− [Mo 2(μ 2-S 2) 2 (S 2CNME 2) 4] (TCNQ) 3

• Published in: Inorganica Chimica Acta Vol. 278; no. 1; pp. 108 - 112
• Main Authors: Conan, Françoise, Pala, Jean Sala, Garland, Maria-Teresa, Baggio, Ricardo
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.08.1998; Elsevier
• Subjects: Chemical Sciences; Crystal structures; Dithiocarbamato complexes; TCNQ anion complexes; Molybdenum complexes; Dinuclear complexes
• ISSN: 0020-1693; 1873-3255; 0020-1693
• DOI: 10.1016/S0020-1693(97)06173-2

The reaction of compounds [Mo 2(μ 2-S 2) 2(S 2CNR 2) 4](BF 4) 2 ( 1) (a R = Me, b R= Et) with 2 equiv. of LiTCNQ in methanol results in the formation of complexes [Mo 2(μ 2-S 2) 2(S 2CNR 2) 4](TCNQ) 2 ( 2). Further reaction of 2 with TCNQ yields the derivatives [Mo 2(μ 2-S 2) 2 (S 2CNR 2) 4](TCNQ) 3 ( 3). Compounds 2 and 3 were characterized fully by microanalytical, IR and electron spin resonance studies. The single crystal structure of the green product 3a·2 CH 3CN was determined by X-ray diffraction methods. The TCNQ units form centrosymmetrical trimers with a slipped conformation and an interplanar distance of 3.16 Å. In the [(TCNQ) 3] 2− anion, the bond lengths agree with an almost complete delocalization of the charge between three essentially identical TCNQ units. The trimers stack with an intertrimer distance of 3.56 Å. The centrosymmetric dinuclear cation is characterized by an MoMo distance of 2.817(2) Å in agreement with a metal-metal single bond. The molybdedum atoms are bridged by two μ 2-S 2 2 ligands which presnet a quite normal bridge distances S-S of 2.001 ( 2) Å.