Patent · US Expired

Aqueous hexasubstituted guanidinium chlorides and methods for their preparation and use

US6235934A · kind A · utility

11Cited by
4References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 17, 1998
Grant dateMay 22, 2001
Priority date
Expiry dateDec 17, 2018

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07C277/00
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

Hexasubstituted guanidinium chlorides are prepared by a method which affords them in high yield as aqueous solutions, optionally also containing alkali metal chlorides. The solutions may be employed as sources of hexasubstituted guanidinium salts useful as phase transfer catalysts for the reaction of alkali metal salts of dihydroxyaromatic compounds with substituted imides to form polyetherimides or their intermediates.

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