Patent · US Expired

Process for the preparation of 4-substituted 1-aryl-5-amino-pyrazoles

US4820847A · kind A · utility

13Cited by

0References

9Claims

0Family size

Assignee

BAYER HEALTHCARE LLC · DE

Inventors

Bernd Gallenkamp · Wuppertal, DE
Heinz-Jurgen Wroblowsky · Langenfeld, DE
Dietmar Bielefeldt · Ratingen, DE

Key dates

Filing date	Sep 3, 1987
Grant date	Apr 11, 1989
Priority date	—
Expiry date	Sep 3, 2007

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC07D231/44
WIPO fieldOrganic fine chemistry
WIPO sectorChemistry

Abstract

4-susbstituted 1-aryl-5-amino-pyrazoles of the formula ##STR1## in which R.sup.1 represents hydrogen or alkyl, PA0 R.sup.2 represents alkyl or halogenoalkyl, and PA0 Ar represents in each case polysubstituted phenyl or polysubstituted pyridyl, some of which are known, are obtained when an arylhydrazine hydrohalide of the formula EQU AR--NH--NH.sub.2 x HHal in which PA0 Hal represents halogen, and PA0 Ar has the abovementioned meaning, is reacted with an acrylonitrile derivative of the formula ##STR2## in which R.sup.1 and R.sup.2 have the abovementioned meaning, and PA0 R.sup.3 and R.sup.4, independently of one another, in each case represent alkyl or phenyl, or PA0 R.sup.3 and R.sup.4, together with the nitrogen atom to which they are bound, represent a saturated heterocyclic ring, at temperatures between 60.degree. C. and 90.degree. C.

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