Cadmium diethyl dimethyl

Cadmium dimethyl. Cadmium diethyl Cadmium di-n-propyl Cadmium di-u-butyl Cadmium di-isoamyl Cadmium di-isobutyl... 

Many organocadmium compounds are known but few have been of commercial importance. Wanklyn first isolated diethyl cadmium in 1856. The properties of this and other dialkylcadmiums are listed in Table 4. In general, these materials are prepared by reaction of an anhydrous cadmium halide with a Grignard or alkyUithium reagent followed by distillation of the volatile material in an inert atmosphere or in vacuo. Only the liquid dimethyl compound is reasonably stable and then only when stored in a sealed tube. Dimethylcadmium is mildly pyrophoric in air and produces dense clouds of white, then brown, cadmium oxide smoke, which is highly toxic if breathed (45). When dropped into water, the liquid sinks in large droplets that decompose with a series of small explosive jerks and pops. For this reason, and particularly because of the low thermal stability, most dialkylcadmium materials are prepared and used in situ without separation, eg, in the conversion of acid chlorides to speciality ketones (qv) ... 

Both 1 1 and 2 1 complexes of Af,.ZV-diethyl- and N,iV-dimethyl-thiourea with zinc, cadmium and mercury halides have been prepared. The 2 1 complexes are either monomeric and tetrahedral or polymeric and halogen-bridged with octahedral metal coordination the 1 1 complexes also possess a polymeric, halogen-bridged structure, but with tetrahedral metal coordination.894 5... 

The remaining diethyl ether is fractionally distilled off from the dimethyl-cadmium at atmospheric pressue (bp 34-35°C). Distillation is continued until pure dimethylcadmium has started to cross the still head (bp 105-106°C)—at which point the argon flow through the paraffin-oil bubbler is increased to a rapid purge while the oil bath is lowered quickly to prevent distillation of further product. The system is allowed to stand for several minutes to allow any dimethylcadmium in the Vigreux column to drain back down into the distillation flask and valve D is then closed. A small amount of dimethylcadmium will decompose during this distillation process, as witnessed by the cadmium metal residue formed in the distillation flask, but this is unavoidable and does not significantly affect the subsequent yield of product. 

The heats of formation of cadmium dimethyl and diethyl have been determined by Skinner et and lead to (C-Cd) = 24... 

Aryl tellurium halides react with aliphatic and aromatic Grignard reagents, with ethenyl magnesium halides , with ethynyl magnesium bromide with dimethyl and diethyl cadmium , with 2-(diphenylphosphino)-phenyl lithium, and with phenyl mercury chloride to produce aryl organo telluriums (p. 416). 

Cadmium dimethyl OT-Xylidine Triphenylarsine Titanium tetrachloride Tin tetraethyl Stannic chloride Diethyl selenide Bismuth triethyl Diethyl telluride Nickel carbonyl Iron carbonyl Lead tetraethyl... 

Spin-lattice relaxation rates for cadmium in organometallic compounds have been measured for neat dibutylcadmium (13) (T 0.2 sec - 5 sec Temp = 228 K Bq = 2.1 Tesla) and dimethyl-, diethyl-, and dipropylcadmiura (15) (T = 3.5-0.6 sec Bq = 2.35 Tesla). From NOE measurement, neat dimethylcadmium experiences no dipolar relaxation (15). Mechanisms contributing to relaxation are thought to be chemical exchange and chemical shielding anisotropy however, their relative importance has not been published for these compounds. 

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