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The reaction of an organic substrate with phosgene is called phosgenation. [9] Phosgenation of diols give carbonates (R = H, alkyl, aryl), which can be either linear or cyclic: n HO−CR 2 −X−CR 2 −OH + n COCl 2 → [−O−CR 2 −X−CR 2 −O−C(=O)−] n + 2n HCl. An example is the reaction of phosgene with bisphenol A to form ...
The main polycarbonate material is produced by the reaction of bisphenol A (BPA) and phosgene COCl 2. The overall reaction can be written as follows: The first step of the synthesis involves treatment of bisphenol A with sodium hydroxide, which deprotonates the hydroxyl groups of the bisphenol A. [6] (HOC 6 H 4) 2 CMe 2 + 2 NaOH → Na 2 (OC 6 ...
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 ...
Organic carbonates are not prepared from inorganic carbonate salts. [citation needed] Two main routes to carbonate esters are practiced: the reaction of an alcohol (or phenol) with phosgene (phosgenation), and the reaction of an alcohol with carbon monoxide and an oxidizer (oxidative carbonylation).
These reactions proceed via the intermediacy of a carbamoyl chloride (RNHC(O)Cl). Owing to the hazardous nature of phosgene, the production of isocyanates requires special precautions. [1] A laboratory-safe variation masks the phosgene as oxalyl chloride. [5]
Carbamoyl chlorides are prepared by the reaction of an amine with phosgene: 2 R 2 NH + COCl 2 → R 2 NCOCl + [R 2 NH 2]Cl. They also arise by the addition of hydrogen chloride to isocyanates: RNCO + HCl → RNHCOCl. In this way, carbamoyl chlorides can be prepared with N-H functionality.
Traces of a toxic, colorless gas were found at the headquarters of Sweden’s security agency where a suspected gas leak last week forced authorities to evacuate some 500 people from the facility ...
Phosgene (carbonyl dichloride, Cl–CO–Cl) is a very toxic gas that is the dichloride of carbonic acid (HO–CO–OH). Both chlorine atoms in phosgene can undergo reactions analogous to the preceding reactions of acyl halides. Phosgene is used a reactant in the production of polycarbonate polymers, among other industrial applications.