Patent · US Expired

Process for preparing alkyl isocyanates

US4514339A · kind A · utility

11Cited by
3References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 10, 1984
Grant dateApr 30, 1985
Priority date
Expiry dateMay 10, 2004

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07C263/04
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

Process for the production of alkyl isocyanates which can be defined by the general formula: R--N.dbd.C.dbd.O wherein R is an alkyl radical having from 1 to 4 carbon atoms by thermal decomposition of phenyl-N-alkyl urethans which can be defined by the general formula: ##STR1## wherein R has the above defined meaning. Said thermal decomposition is carried out without any substance having a catalytic activity being present in the decomposition reaction, by heating to a temperature of from 180.degree. C. to 210.degree. C. under the atmospherical pressure or a slightly reduced pressure, a mixture of phenol and phenyl-N-alkyl urethan, in a molar ratio of the former to the latter equal to or nearly equal to 1:1, removing by vaporization the phenol and the alkyl isocyanate from said vaporized products and maintaining in the reaction mixture, substantially throughout the thermal decomposition a molar ratio of phenol to phenyl-N-alkyl urethan not lower than about 1:1.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.