Diphosgene, trichloromethyl

Diphosgene, trichloromethyl chloroformate C13C0C(0)C1 Reported as an alternative to the use of oxalyl chloride with the advantage of being a dense liquid with low volatility262... 

Exceptions to this rule-of-thumb may occur if either diphosgene (trichloromethyl... 

Diphosgene (Trichloromethyl chloroformate), CICOOCCI0, Mol. wt. 197.85, b.p. 128°, 49°/50 mm. toxic, asphyxiating gas used in the first world war as a poison gas. This reagent is generally prepared by chlorination hv) of methyl formate or methyl chloroformate. 

Oxazolidinones 593, which represent potential chiral auxiliaries, have been prepared with diphosgene (trichloromethyl chloroformate) [418, 419). 

An article entitled Facile Conversion of Carboxamides to Nitriles [1053] describes the ready conversion of alkyl, benzylic, aryl, and heteroaryl carboxamides bearing various functionalities to the corresponding nitriles in good yields of 76-96% using liquid diphosgene (trichloromethyl chloroformate) as the dehydrating agent. In many cases, the procedure does not require an extraction step, and hence offers a very simple work-up. 

Trichloromethyl chloroformate (diphosgene) is used as a safe substitute for highly toxic phosgene gas. The latter is generated in situ by addition of catalytic amounts of tertiary amines or amides, or active carbon. Diphosgene also disproportionates to 2 equivalents of phosgene on heating above 250°C. 

R Katakai, Y Iizuka. An improved rapid method for the synthesis of N-carboxy a-amino acid anhydrides using trichloromethyl chloroformate. (diphosgene). J Org Chem 50, 715, 1985. 

Scheme 9 Reaction of an Amino Acid with Trichloromethyl Chloroformate (Diphosgene) To Produce N-Carboxyanhydrides...

The preference of the Germans during the war of 1914-18 for employing trichloromethyl chloroformate (diphosgene) rather than... 

Green Cross Gases. This includes substances with a high vapour tension and great toxic power on the respiratory tract phosgene, trichloromethyl chloroformate (diphosgene), chloro-picrin, etc. 

Trichloromethyl CI3C-0-C-CI II 0 503-38-8 125/748 Phosgene substitute (also called diphosgene )... 

The reversibility of the decomposition of Diphosgene into carbon tetrachloride and carbon dioxide is still a controversial topic. However, the production of phosgene by reaction of carbon tetrachloride and carbon dioxide over catalysts such as Lewis acids was recently claimed in Russian patents (Ref. 32). The reaction is assumed to proceed through the formation of trichloromethyl chloroformate or bis(trichloromethyl) carbonate. 

Phosgene, as well as the easier to handle diphosgene (chloroformic acid trichloromethyl ester) or triphosgene (carbonic acid bis(trichloromethyl) ester) transform primary, secondary and tertiary amides and thioamides to chloromethyleneiminium chlorides (25 equation 15), whereby the reaction with thioamides is of broader scope and proceeds with fewer side reactions. The amide chlorides derived from primary and secondary amides can lose HCl, giving nitriles or imidoyl halides, respectively. /V-Sub-stituted formamides can be converted to isonitriles via amide halides. ... 

Trichloromethyl chloroformate (DP, diphosgene) was first used in the summer of 1915. It eventually replaced monochloromethyl chloroformate in German gas shells and was used extensively through the end of the war. 

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