Patent ID: 8399670

Claim:
A process for the preparation of dibrominated perylene diimide compound represented by the structures of formula 1,6-3 and 1,7-3; wherein R 1 and R 2 are the same or different substituted or unsubstituted linear or branched alkyl group, substituted or unsubstituted saturated carbocyclic or heterocyclic ring or aryl; comprising the steps of a) brominating compound of formula 1 wherein R 1 and R 2 are as defined above; in the presence of bromine and a chlorinated solvent at reflux for a period of time sufficient to obtain a mixture comprising compounds of formula 1,6-3 and 1,7-3; and b) separating between 1,6-3 and 1,7-3 regioisomer compounds by recrystallizing compound of formula 1,7-3 yielding crystalline pure perylenediimide of formula 1,7-3, thereby separating between said regioisomer compounds.