Disilver diazomethane

Group IV. C-donor ligands. The highly explosive yellow-orange disilver diazomethane has been obtained in high yield (equation 48).216 The i.r. spectrum suggests... 

Disilver diazomethane has also been synthesized. When treated with an alkyne, it produces the corresponding silver acetylide.80... 

Two other syntheses of dimethyl squarate have been reported.2 One such method involves the formation of the disilver salt of squaric acid followed by treatment with methyl iodide. This process, unfortunately, is laborious as well as costly. The other synthesis involves the reaction of squaric acid with diazomethane. This reaction not only gives a lower yield, but is inherently unsuited for large scale preparations. The synthesis presented here provides a convenient and inexpensive route to the preparation of dimethyl squarate, and is also suitable for large scale synthesis.4 One should take precautions when synthesizing or using dialkyl squarates, particularly dimethyl squarate, since they are known to cause severe contact dermatitis.5 Thus, all procedures should be carried out in the hood and protective clothing and gloves should be worn. 

Diazocarbonyl and diazophosphoryl compounds react with silver (ii) oxide easily (Schollkopf and Rieber, 1969). In diazomethane, both H-atoms are replaced with silver acetate in a mixture of ether and pyridine (Blues et al., 1974). Mono- and disilver diazo compounds are often used for C-alkylation (see examples given by Regitz and Maas, 1986, Sect. 14.6). 

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