Patent · US Expired

Process for the preparation of 3-hydrazino-1,2-benz-isothiazole 1,1-dioxides

US4667041A · kind A · utility

1Cited by

4References

6Claims

0Family size

Assignee

BAYER HEALTHCARE LLC · DE

Inventors

Herbert Salzburg · Leichlingen, DE
Manfred Hajek · Leverkusen, DE
Gerd Hanssler · Leverkusen, DE

Key dates

Filing date	Feb 28, 1985
Grant date	May 19, 1987
Priority date	—
Expiry date	Feb 28, 2005

Classification

Technology area (CPC A)Human Necessities
CPC primaryA01N43/80
WIPO fieldOrganic fine chemistry
WIPO sectorChemistry

Abstract

A process for the preparation of a 3-hydrazino-1, 2-benzisothiazole 1,1-dioxide of the formula ##STR1## in which R.sup.1 and R.sup.2 each independently is hydrogen, alkyl, halogen, amino, hydroxyl or carboxyl, and PA1 R.sup.3 and R.sup.4 each independently is hydrogen, alkyl, cycloalkyl or aryl, comprising reacting a 3-keto-2H,3H-1,2-benzisothiazole 1,1-dioxide of the formula ##STR2## with a hydrazine of the formula ##STR3## in a molar ratio of 1:1 to 1:50, in an inert solvent, at a temperature between 75.degree. C. and 200.degree. C. and for a reaction time of 15 to 40 hours. The products, some of which are known, are fungicidally active and can also be used as intermediates.

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