Technetium complexes with 2-mercapto-methyltetrazolate

2-Mercapto-methyltetrazolate, Smetetraz(-), acts as monoanionic, monodentat e ligand in a number of technetium compounds. Anionic Tc-V complexes of the types [TcO(Smetetraz)(4)](-) and [TcN(Smetetraz)(4)](2-) are formed when ( Bu4N)[(TcOCl4)-O-V] or (Bu4N)[(TcNCl4)-N-VI], respectively, react with Na(S metetraz). Reduction of the metal takes place in the latter case. (Bu4N)(2) [TcN(Smetetraz)(4)] crystallises in the monoclinic space group Pc (a = 9.70 1(5), b = 17.570(5), c = 16.821(10)Angstrom, beta = 96.50(3)degrees, Z = 2) . The Tc atom is situated 0.580(3) Angstrom above the basal plane of a squa re pyramid which is formed by the sulfur atoms and the nitrido ligand as it s apex. The Tc-S bond lengths lie between 2.384(3) and 2.410(3) Angstrom. [ Tc(PPh3) (Smetetraz)(3)(CH3CN)] is formed during the reaction of [TcCl3(PPh 3)(2)(CH3CN)] with NaSmetetraz as blue needles with co-crystallised solvent toluene (space group C2/c, a = 24.188(4), b = 14.373(1), c = 25.617(5) Ang strom, beta = 109.48(1)degrees, Z = 8). The metal atom is coordinated by PP h3 and CH3CN in the axial position of a trigonal bipyramid. All three aryl rings are on the sterically less strained side of the plane defined by the sulfur atoms. The Tc-S bond lengths range between 2.233(2) and 2.247(2) Ang strom.