Polymeric thiolate complexes of Group 12 metals. Crystal and molecular structures of catena-[µ-(3-dimethylammonio-1-propanethiolate)]-dichloro-cadmium(II) and bis[3-(dimethylammonio)propyl] disulphide tetrabromocadmate(II)

The complexes [MX2{µ-S(CH2)3NH(CH3)2}] and corresponding disulphides [{(CH3)2HN(CH2)3S}2][MX4](M = ZnII, CdII, or HgII; X = Cl or Br) have been prepared or characterized. Both families of compounds are isostructural with [CdCl2{µ-S(CH2)3NH(CH3)2}] and [{(CH3)2HN(CH2)3S}2][CdBr4] respectively. Crystals of the former are monoclinic, space group P21/n, with a= 15.995(3), b= 6.532(2), c= 10.237(2)Å, and β= 95.66(2)°. The crystal structure consists of infinite chains of alternating cadmium and sulphur atoms. Each cadmium atom is tetrahedrally co-ordinated to two terminal chlorine atoms and two bridging sulphur atoms. Crystals of the second compound are orthorhombic, space group Pbn21, with a= 23.406(3), b= 13.531(2), and c= 6.738(1)Å. The crystal structure consists of discrete bis[3-(dimethylammonio)propyl] disulphide dications and tetrabromocadmate(II) anions linked by hydrogen-bond interactions that give rise to a staircase-like framework.