Patent · US Expired

Method for producing N-substituted 2-pyrazoline-5-one

US6515139B1 · kind B1 · utility

1Cited by

2References

6Claims

0Family size

Assignee

BASF SE

Inventors

Hans Rupert Merkle · Ludwigshafen, DE
Erich Fretschner · Neckarsteinach, DE
Knut Koob · Mutterstadt, DE

Key dates

Filing date	May 13, 2002
Grant date	Feb 4, 2003
Priority date	—
Expiry date	Nov 20, 2022

Classification

Technology area (CPC A)Human Necessities
CPC primaryA61P25/28
WIPO fieldOrganic fine chemistry
WIPO sectorChemistry

Abstract

The present invention relates to a process for preparing N-substituted 2-pyrazolin-5-ones of the formula I where R has the meaning given in claim 1, which comprises reacting a compound of the formula II where R, X and Y have the meanings given in claim 1, at elevated temperature with a molar excess of alkali metal hydroxide in an aqueous reaction medium and then adjusting the pH to pH&lE;6 by adding an acid.

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