Chromium, xanthate structures

This section describes the structural chemistry of 14 molecular structures, 3 of chromium, 8 of molybdenum, and 3 of tungsten. The only binary xanthate structures are those of chromium, all other structures are at least ternary in nature. For the chromium and tungsten structures, conventional monodent-ate and bidentate coordination modes of the xanthate ligand are found. By contrast, a rich, diverse, and fascinating coordination range is observed for the... 

Only four structures are available for the aluminum-group xanthates. The crystal stmctures of Ga(S2COEt)3 and In(S2COEt)3 (200) are isomorphous with each other and with the chromium analog, Cr(S2COEt)3 (31), which is shown in Fig. 10. Thus, each molecule has crystallographic threefold symmetry and essentially equivalent Ga—S [2.405(2) and 2.465(2) A] and In—S [2.574(1) and... 

Dinuclear niobium sulfido and selenido dithiophosphates, Nb2Q4[S2P(OR)2]4,75,76 (Q = S, Se R = Et) (also xanthates and dithiocarbamates) have been prepared but no crystal structure was reported. Optically active chromium complexes, Cr[S2P(OR)2]3 derived from Z)-borneol and L-menthol, have been described.77... 

Earlier structural studies of carbohydrates by CD involved introduction of suitable chromophores into the sugar molecule thereby affording derivatives which exibit Cotton effects. These include, among others, xanthates (4-8) or azides (9). Later it was found that some metal ions (10), i.e. copper (11,13), vanadate (14), chromium (15), molybdate (16-22), nickel (23) or cobalt (24,25) ions form complexes with carbohydrates, which show appreciable Cotton effects. 

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