Patent · US Expired

Process for preparing 4,4'-dinitrostilbene-2,2'-disulphonic acid

US5808141A · kind A · utility

0Cited by

3References

7Claims

0Family size

Assignee

BAYER HEALTHCARE LLC · DE

Inventors

Albert Schnatterer · Leverkusen, DE
Helmut Fiege · Leverkusen, DE

Key dates

Filing date	Jul 21, 1997
Grant date	Sep 15, 1998
Priority date	—
Expiry date	Jul 21, 2017

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC07C303/32
WIPO fieldOrganic fine chemistry
WIPO sectorChemistry

Abstract

The new process for preparing 4,4'-dinitrostilbene-2,2'-disulphonic acid and salts thereof by oxidation of 4-nitrotoluene-2-sulphonic acid with an oxidant in the presence of strong bases is characterized in that the oxidation is carried out in a mixture of water and an organic solvent selected from the group consisting of alcohols, ethers and mixtures thereof.

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