| 摘要 |
<p>1,137,292. Isocyanic acid. STAUFFER CHEMICAL CO. 5 Jan., 1966 [18 Jan, 1965], No. 524/66. Heading C1A. Stabilized isocyanic acid is produced by contacting carbamoyl chloride with a Lewis base, the basicity of which is sufficient to abstract hydrogen chloride from the carbamoyl chloride, but not sufficient to cause trimerization of the so-formed isocyanic acid. The weak Lewis base may be an ether (e.g. diethylether), a polyether (e.g. a dialkoxyalkane such as 1,2-dimethyoxethane), a polymeric ether (e.g. a polyoxyethylene resin), a thioether (e.g. as a dialkylsulphide such as diemthyl-sulphide, diethylsulphide or di-n-propyl sulphide) and substituted amides (e.g. an N,N-dialkyl amide such as N,N-dimethylacetamide). The carbamoyl chloride may be generated just before use by reacting phosgene with ammonia in a heated reaction zone and collecting the carbamoyl chloride in a water cooled receiver.</p> |
