Self-assembly of organocadmium compounds

Dimethylcadmium forms an 1 1 adduct with dioxane which is used in metal-organic chemical vapor deposition of cadmium sulfide. This material is a self-organized monodimensional array, 23, formed via O Cd bonds (2.88 and 2.75 A). The coordination geometry around cadmium is rather curious the methyl groups are arranged linearly (C-Cd-C 173.0°), other angles being as follows O-Cd-0 114.2°, C-Cd-O 88.8° and 93.5°. Some association between dimethylcadmium and dioxane is also maintained in benzene solution [44]. 

Little information is available about the structure of organocadmium halides. They are poorly soluble in organic solvents, suggesting supramolecular association in the solid state. Some organocadmium halides with bulky substituents were found 

In the solid state pentafluorophenylcadmium hydroxide, CeFsCdOH, is a tetramer, 25, based on a Cd404 cubane skeleton (Cd-O 2.204-2.248 A), reminiscent of the structures of organozinc alkoxides [46]. An organocadmiiun-sulfur cubane supermolecule, [C6F5CdSCPPh3]4, and related self-assembled anionie species have also been reported [47]. 

Dimeric [(cT-C5Me5)CdN(SiMe3)2]2 contains a nearly planar, asymmetric Cd2N2 ring, 26, (Cd-N 2.257 and 2.338 A) with trigonal planar coordination of the cadmium atoms [48]. 

Dimethylcadmium reacts with gallium tris(di-terr-butyl phosphide), Ga(PBu 2)3, to give a trimeric derivative [MeCdPBuSJr crystal structure determination revealed cyclic self-assembly, 27, with trigonally planar coordinated cadmium and a tendency of bond length alternation in the six-membered ring (Cd-P 2.568 and 2.586 A) [49]. This compound serves as a precursor for cadmium phosphide (Cd3P2) nanoparticles [49a]. 

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