Diphosgene

Diphosgene can be prepared by the complete chlorination of methyl formate (or methyl 

The compound reacts with alcohols, phenols and amines to form products similar to those obtained from the corresponding reaction with COCI [1358]. Depending upon the conditions and stoicheiometry, carbonates and chloroformates [612,1380], carbamates [1380], isocyanates [1184] and ureas [938] can be obtained with diphosgene, in addition to more complicated products such as carbamoyl chlorides, imidic chlorides, carboxylic acid chlorides, isonitriles and IV-carboxy-Q-amino acid anhydrides [1358]. 

Diphosgene has not been prepared from phosgene itself, but its detailed preparation from the action of dichlorine on methyl chloroformate has been described [1184]. However, diphosgene is now readily available commercially from regular suppliers. 

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Oligomers of phosgene, such as diphosgene [503-38-8] (COCl2)2, have found use in the laboratory preparation of isocyanates. Carbamoyl chlorides, A[,A/-disubstituted ureas, dimethyl- and diphenylcarbonates, and arylsulfonyl isocyanates have also been used to convert amines into urea intermediates, which are subsequendy pyroly2ed to yield isocyanates. These methods have found appHcations for preparation of low boiling point aUphatic isocyanates (2,9,17). 

Diakyl carbamyl chlorides Diakyl aluminum hydrides Diborane Dibromoketone Dichloromethyl chloroformate Diphosgene Fuming nitric acid Gngnard reagents Hydrides nonvolatile... 

One step polymerization using phosgene or diphosgene as coupling agents. Macromolecules. 21, 1925-1929, 1988. 

Solubility Insoluble in water soluble in organic solvents, lipids, organophosphorus compounds, mustards, phosgene, diphosgene, and Cl2. 

Pulmonary/ choking agents phosgene, chlorine, diphosgene, chloropicrin, oxides of nitrogen, and sulfur dioxide. 

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. 

Although the synthesis of the oxazolidinone 159 appeared to be well established, the scale-up of the reaction gave poorly reproducible results. The synthesis was much more efficient using diphosgene and a catalytic amount of activated charcoal <06S885>. 

The convenient synthesis of dichloroquinazolines 52 from anthranilonitriles by reaction with diphosgene was also applied to fusion of pyrimidine rings onto other heterocyclic aminonitriles <06SL65>. 

Damle, Suresh B. "Safe Handling of Diphosgene, Triphosgene." Chemical Engineering News 71 (8 Feb 1993) 4. 

Green Cross No. 1 (Griinkreuz 1—German WWI Shell) Diphosgene with or CIO-A... 

Green Cross No. 2 (Griinkreuz 2—German WWI Shell) Phosgene (60%), Diphosgene (30%) and Diphenylchloroarsine (10%) Mixture ... 

Griinkreuz (Green Cross) Diphosgene with or without Chloropicrin and/or Bromomethylethyl Ketone Mixture ... 

Guides for Emergency Response Chemical Agent or Weapon Diphosgene and Phosgene... 

LCt50 3,000 mg-min/3 for resting persons. Since the effects of diphosgene are cumulative, the Ct does not significantly change with variations in time of exposure. 

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