A novel metallacycle, 1,2,5,3-cobaltadithiazole. Formation, structure, and properties of (η5-cyclopentadienyl or η5-pentamethylcyclopentadienyl)(1-phenylmethanimine-N,1-dithiolato)cobalt(III)

Article abstract of DOI:10.1016/0022-328X(94)80132-0

(η⁵-Cyclopentadienyl)(1-phenylmethanimine-N,1-dithiolato)cobalt(III), 5-C5R5)> (1a: R = H or 1b: R = CH3), which contain a 1,2,5,3-cobaltadithiazole ring were synthesized in the reactions of 5-C5R5)Ln> Ln = (CO)2 or 1,5-cyclooctadiene) with two types of heterocyclic compounds: (1) compounds with a partial structure of -S-N=C(Ph)-S- or with similar structures; and (2) compounds which give benzonitrile sulfide on thermolysis or photolysis.The crystals of 1b are orthorhombic of space group P_2,2,2 with a = 14.936 Angstroem, b = 14.262 Angstroem, c = 8.078 Angstroem and Z = 4.The structure was solved and refined to R = 0.038 and R_w = 0.040 by using 3981 independent reflections.The structure of 1,2,5,3-cobaltadithiazole is similar to that of 1,2,5-cobaltadithiolenes.The 1,2,5,3-cobaltadithiazole ring is almost planar and perpendicular to cp^*.The cobaltadithiazoles undergo a reversible one electron reduction which is ascribed to the process from Co^III to Co^II.The halfwave potential of -1.34 V versus Ag<*>0.1 mol dm^-3 AgClO4 for the reduction of 1b is less negative than that of the cobaltadithiolene with a similar structure.This shows that the nitrogen atom in the ring attracts electrons and causes the cobaltadithiazole ring to be electron-dificient. Key words: 1,2,5,3-Cobaltadithiazole; Metallacycle; Cobalt; Dithiolate