Patent · US Expired

Process for producing bismethine isoindolines

US4500718A · kind A · utility

6Cited by
5References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 23, 1983
Grant dateFeb 19, 1985
Priority date
Expiry dateSep 23, 2003

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC09B57/04
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

A process for producing bismethine isoindolines of the formula ##STR1## in which process the condensation of 1 mol of any one of the compounds of the formulae ##STR2## with 2 mols of a cyanomethylene compound of the formula NC--CH.sub.2 --R.sub.1 or NC--CH.sub.2 --R.sub.2, or with 1 mol of a cyanomethylene compound of the formula NC--CH.sub.2 --R.sub.1 and 1 mol of a cyanomethylene compound of the formula NC--CH.sub.2 --R.sub.2, wherein the symbols have the meanings defined in the specification, is performed in a polar solvent in the presence of a strong base, and the bismethine isoindoline obtained is isolated from the reaction mixture by hydrolysis. The bismethine isoindolines are suitable for pigmenting high-molecular organic material, particularly lacquers.

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