| 摘要 |
1,054,673. Carbamic esters. PROGIL. Aug. 21, 1963 [Aug. 23, 1962], No. 33151/63. Heading C2C. Compounds R<SP>1</SP>R<SP>2</SP>NCOOR<SP>3</SP>, where R<SP>1</SP> and R<SP>2</SP> are alkyl or aryl, or one may be hydrogen, and R<SP>3</SP> is alkyl or aryl, are prepared by reacting, at a temperature maintained at 0-60‹ C., R<SP>3</SP>OH with R<SP>1</SP>R<SP>2</SP>NCO Halogen in the absence of a hydracid acceptor, eliminating the H Halogen, as it is formed or after formation of the ester, by distillation or by entrainment with an inert gas. Solvents may be present and may be used to entrain the H Halogen when it is removed by distillation; or an excess of the carbamyl halide may be so used. Examples prepare α-naphthyl mefhylcarbamate. Reference has been directed by the Comptroller to Specification 841,141. |
