99688-14-9Relevant academic research and scientific papers
Cadmium-113 nuclear magnetic resonance spectroscopic study of mixed-ligand tetranuclear clusters of the type [Cd4(EPh)x(E′R)10-x]2- and of the mixed-metal clusters [CdxZn4-x(SPh)10]2-
Dean, Philip A. W.,Vittal, Jagadese J.
, p. 514 - 519 (2008/10/08)
The synthesis of (Me4N)2[Cd4(SePh)10] (1) is described. The 113Cd-enriched compound (1*) undergoes ligand redistribution with the sulfur analogue (2*) to give the series [113Cd4(SPh)x(SePh)10-x] 2- (x = 0-10), in which each member is characterized by a single line in the 44.4-MHz 113Cd NMR spectrum at ambient probe temperature. The same complexes can be made in solution by redox reaction of 1* with Ph2S2 or 2* with Ph2Se2. Similarly, at ambient probe temperature, resolvable single 113Cd NMR lines characterize the species [Cd4(SPh)x(SR)10-x]2- (R = Me, x= 8-10; R = Bu, x = 4-10; R = PhCH2, x = 7-10; R = 2-C6H4Me, x = 0-10), produced from 2 or 2* and R2S2, [Cd4(SePh)x(SBu)10-x] (x = 5-10), produced from 1 and Bu2S2, [113Cd4(SPh)x(TePh)10-x] 2- (x = 8-10), produced from 2* and Ph2Te2, and [113Cd4(SePh)x(TePh)10-x] 2- (x = 7-10), produced from 1* and Ph2Te2. The observed or extrapolated 113Cd NMR chemical shifts of [Cd4(ER)10]2-, in which the kernels are (RE)Cd(μ-ER)3, are close to those of [Cd(ER)4]2-, confirming that 113Cd NMR is not very sensitive to the bridging/terminal nature of the bound groups, as found in earlier work. When mixtures of [Cd4(SPh)10]2- and [Zn4(SPh)10]2- were reinvestigated with use of 113Cd enrichment, only three cadmium-containing species could be detected by 113Cd NMR. These are probably [113CdxZn4-x(SPh)10]2- (x = 2-4). The relevance of this nonstatistical metal distribution to that in zinc-cadmium metallothionein is discussed.
