Transition metals, dithiocarbamate complexes molybdenum

It is not clear when dithiocarbamates were first prepared, but certainly they have been known for at least 150 years, since as early as 1850 Debus reported the synthesis of dithiocarbamic acids (1). The first synthesis of a transition metal dithiocarbamate complex is also unclear, however, in a seminal paper in 1907, Delepine (2) reported on the synthesis of a range of aliphatic dithiocarbamates and also the salts of di-iTo-butyldithiocarbamate with transition metals including chromium, molybdenum, iron, manganese, cobalt, nickel, copper, zinc, platinum, cadmium, mercury, silver, and gold. He also noted that while dithiocarbamate salts of the alkali and alkali earth elements were water soluble, those of the transition metals and also the p-block metals and lanthanides were precipitated from water, to give salts soluble in ether and chloroform, and even in some cases, in benzene and carbon disulfide. 

Transition metal dithiocarbamate complexes were probably first prepared in 1907 by Delepine (2) and over the following century, dithiocarbamate complexes of all the transition elements have been prepared and in a wide range of different oxidation states (Table 1). Perhaps most impressive is their ability to stabilize molybdenum in seven oxidation states ranging from - -6 to 0 (Fig. 24). 

Electrochemical recognition, 39 80 anions, macrocyclic and acyclic polycobalti-cinium ligand systems, 39 134-140 cations, 39 81-133 ammonium cation, 39 128-133 crown ether and bis crow ether ligands containing bipyridyl transition metal recognition sites, 39 111 crown ether dithiocarbamate and dithi-olene complexes, 39 123-124 di-h-cyclopentadienyl-molybdenum(IV) and -tungsten(IV) crown ether complexes, 39 107-108... 

Another widely utilized method involves the oxidative-addition of thiuram disulhdes to metal centers (Eq. 15) a reaction that has been reviewed by Victoriano (25, 170). Dithiocarbamate complexes of a number of transition metals can be prepared via this method, with examples at vanadium (171-173), molybdenum (174-180) and tungsten (181-183) being particularly prevalent. 

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