Dichlorodimethyl Ether Chloromyl

Addition of phosgene to the carbonyl group of a carboxylic ester, e.g. methyl formate, followed by elimination of carbon dioxide, generates 1,1-dichlorodimethyl ether (Chloromyl ) 1364, a liquid phosgene equivalent (bp 85 °C). Chloromyl is 

Using Chloromyl , phenylacetic and adipic acids (e.g. 1365) or a-keto acids (e.g. 1368) are converted to their acid chlorides with volatilization of hydrogen chloride and methyl formate 1367 (bp 32 °C) [1033]. 

Symmetric Anhydrides and Esters. Nucleophilic Substitution of Acyl Chloroformates 

Anhydrides are typically prepared by the reaction of an acyl halide and a carboxy-late salt [1034], or by the reaction of a carboxylic acid with P2O5 [1035], methoxy-acetylene [1036], or a carbodiimide [1037-1039]. 

A report of the synthesis of acid anhydrides using phosgene gas has also appeared in the literature [1040, 1041]. Nicotinic anhydride 1371 was prepared from nicotinic acid 1370 with phosgene in 87-93% yield, as described in a very detailed 

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