Preparation of perylen-3,4:9,10-tetracarboxylic dianhydride and also of naphtalene-1,8-dicarboximides

US7807836B2 · kind B2 · utility

Assignee

• BASF SE

Inventors

• Bernhard Dung · Havelsee, DE
• Felix Mueller · Bischofswerda, DE
• Arno Boehm · Mannheim, DE
• Willi Helfer · Friedelsheim, DE
• Volker Weyrauch · Deidesheim, DE
• Georg Henning · Ludwigshafen, DE

Key dates

• Filing date: Dec 13, 2007
• Grant date: Oct 5, 2010
• Expiry date: Feb 15, 2028

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C09B57/08
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

A process for preparing perylene-3,4:9,10-tetracarboxylic dianhydride, comprising: dimerizing a naphthalene-1,8-dicarboximide of the formula IIa;reoxidizing the resulting alkali metal salt of the leuco form of the perylene-3,4:9,10-tetracarboxylic diimide of the formula Ia;hydrolyzing the diimide to the tetraalkali metal salt of perylene-3,4:9,10-tetracarboxylic acid in the presence of an inert organic solvent, of an alkali metal base and of water; and subjecting the tetraalkali metal salt of perylene-3,4:9,10-tetracarboxylic acid to the action of an aqueous inorganic acid to convert it into perylene-3,4:9,10-tetracarboxylic dianhydride; wherein R3 is cyclohexyl or phenyl which may each be substituted by up to three C1-C4-alkyl radicals, and the dimerizing is in a substantially homogeneous reaction medium consisting essentially of an apolar aprotic organic solvent and an alkali metal base.