Patent · US Expired

Process for preparing substituted pyridone compounds

US6696552B2 · kind B2 · utility

91Cited by
29References
44Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 27, 2002
Grant dateFeb 24, 2004
Priority date
Expiry dateAug 25, 2022

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S534/02
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

A process which comprises admixing in the absence of a solvent an amine of the formula R1—NH2 and a first ester of the formula wherein R2 is an electron withdrawing group and R3 is an alkyl group; heating the mixture containing the amine and the first ester to form an intermediate compound of the formula admixing the intermediate compound with a base and a second ester of the formula said second ester being present in a molar excess relative to the intermediate compound, said base being present in a molar excess relative to the intermediate compound, and heating the mixture to form a pyridone compound of the formula or a salt thereof. Also disclosed is a process for preparing diazopyridone colorants which comprises preparing a pyridone compound by the above process and reacting the pyridone compound with a diazonium salt to form a diazopyridone compound.

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