Patent · US Expired

Process for preparation of anthraquinones and fluorenones

US4804501A · kind A · utility

2Cited by
2References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 25, 1988
Grant dateFeb 14, 1989
Priority date
Expiry dateApr 25, 2008

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P20/584
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

A process is disclosed for producing cyclized aromatic compounds by the liquid-phase air oxidation of 2-methyl-substituted biphenyls and diphenylmethanes in an acetic acid medium in the presence of a cobalt-manganese-bromine catalyst or a zirconium-cobalt-manganese-bromine catalyst wherein the mole ratio of cobalt-to-manganese is about 1.0:0.1 to about 1.0:10.0 and the ratio of zirconium-to-cobalt is about 0.005:1.0 to about 0.20:1.0, and mole ratio of bromine to total metals of said cobalt-manganese-bromine catalyst or zirconium-cobalt-manganese-bromine catalyst is from about 0.2:1.0 to about 20.0:1.0, which process comprises conducting the reaction in a batch process at a temperature of from 75.degree. C. to about 250.degree. C. at a pressure of from 1 to 100 atmospheres, or continuously in two stages comprising a first-stage reaction at a temperature of about 75.degree. C. to about 200.degree. C. and a second-stage reaction at a temperature of about 150.degree. C. to about 250.degree. C. and recycling the cobalt-manganese catalyst or the zirconium-cobalt-manganese catalyst by oxalate precipitation of the catalyst at temperatures of about 110.degree. C. to about 200.degree. C. pr…

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