Patent ID: 8222406

Claim:
A process for preparing a heterocycle of the following formula (I) by catalytic reaction of an aromatic dinitrile of the following formula (II) with an amino alcohol of the following formula (III): wherein R 1 , R 2 , R 3 , R 4 , R 5 and R 6 , may be the same or different, and are each independently selected from the group consisting of a hydrogen atom, an alkyl group, an aryl group, a —COOH group and an —NH 2 group, and n is an integer of from 0 to 4, wherein said process comprises: initially charging into a reaction vessel the amino alcohol of formula (III) and a catalyst to produce a reaction mixture; adding the aromatic dinitrile of formula (II) into the reaction mixture, which is maintained at a reaction temperature, wherein no solvent other than the amino alcohol of formula (III) is added to the reaction mixture prior to and/or during the catalytic reaction; and after completion of the catalytic reaction, completely replacing, or substantially completely replacing, unreacted amino alcohol of formula (III) with a nonpolar solvent to obtain the heterocycle of formula (I), wherein the unreacted amino alcohol of formula (III) is present in an amount of not more than 20 wt. %, based on a total weight of the heterocycle of formula (I).