Patent · US Expired

Preparation of carbamates from organic carbonates and aromatic ureas

US4567287A · kind A · utility

3Cited by
4References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 8, 1984
Grant dateJan 28, 1986
Priority date
Expiry dateAug 8, 2004

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07C271/06
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

Disclosed is an improved process for the preparation of carbamates by heating an organic carbonate and an aromatic urea or polyurea in the presence of aluminum as catalyst and a promoter comprising a combination of iodine and a mercury salt. High reaction temperatures are avoided by the process and conversions to carbamate products are high. Additionally, the process is economically attractive because even the common aluminum foil can be used as the catalyst. The products prepared by the process can be used in the production of insecticides, and, particularly, as intermediates in the preparation of organic mono- and polyisocyanates.

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