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|Section2= |Section3= |Section7= |Section8= }} Diphosgene is a chemical compound with the formula ClCO2CCl3. This colorless liquid is a valuable reagent in the synthesis of organic compounds. Diphosgene is related to phosgene and has comparable toxicity, but is more conveniently handled because it is a liquid, whereas phosgene is a gas. ==Production and uses== Diphosgene is prepared by radical chlorination of methyl chloroformate under UV light:〔 〕 :Cl-CO-OCH3 + 3 Cl2 —(hv)→ Cl-CO-OCCl3 + 3 HCl Another method is the radical chlorination of methyl formate:〔Lohs, K. H.: ''Synthetische Gifte''; Berlin (east), 1974 (German).〕 :H-CO-OCH3 + 4 Cl2 —(hv)→ Cl-CO-OCCl3 + 4 HCl Diphosgene converts to phosgene upon heating or upon catalysis with charcoal. It is thus useful for reactions traditionally relying on phosgene. For example, it convert amines into isocyanates, secondary amines into carbamoyl chlorides, carboxylic acids into acid chlorides, and formamides into isocyanides. Diphosgene serves as a source of two equivalents of phosgene: :2 RNH2 + ClCO2CCl3 → 2 RNCO + 4 HCl With α-amino acids diphosgene gives the acid chloride-isocyanates, OCNCHRCOCl, or ''N''-carboxy-amino acid anhydrides depending on the conditions.〔Kurita, K. "Trichloromethyl Chloroformate" in ''Encyclopedia of Reagents for Organic Synthesis'' (Ed: L. Paquette) 2004, J. Wiley & Sons, New York. .〕 It hydrolyzes to release HCl in humid air. Diphosgene is used in some laboratory preparations because it is easier to handle than phosgene. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「diphosgene」の詳細全文を読む スポンサード リンク
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