Patent · US Expired

Hydroxylation of phenolic compounds

US5714641A · kind A · utility

2Cited by
2References
34Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 6, 1995
Grant dateFeb 3, 1998
Priority date
Expiry dateJun 6, 2015

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P20/52
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

Phenolic compounds, e.g., phenol, are hydroxylated, preponderantly into the para-isomer, e.g., hydroquinone, by reaction with hydrogen peroxide in the presence of an effective amount of a strong acid and a catalytically effective amount of a keto compound having the formula (II): ##STR1## in which R.sub.1 and R.sub.2, which may be identical or different, are each a hydrogen atom or an electron-donating group; n.sub.1 and n.sub.2, which may be identical or different, are numbers equal to 0, 1, 2 or 3, with the proviso that the two carbon atoms located at the .alpha.-position with respect to the two carbon atoms bearing the --CO group may be bonded together via a valence bond or via a --CH.sub.2 -- group, thereby forming a keto-containing ring member which may either be saturated or unsaturated.

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