Patent ID: 7135577

Claim:
A method for producing a 2-hydrocarbyl-3,3-bis(4-hydroxyaryl)phthalimidine of Formula (I), said method comprising: (A) heating a reaction mixture comprising: (i) a primary hydrocarbyl amine of Formula (II), —R 1 —NH2, (ii) a phenolphthalein compound of Formula (III), wherein R 1 is selected from a group consisting of a hydrogen and a hydrocarbyl group, R 2 is selected from the group consisting of a hydrogen, a hydrocarbyl group, and a halogen, and R 3 is selected from the group consisting of a hydrogen and a hydrocarbyl group; and forming said 2-hydrocarbyl-3,3-bis(4-hydroxyaryl)phthalimidine, wherein the hydrocarbyl group is selected from the group consisting of an alkyl group, a cycloalkyl group, and an aryl group; (B) forming an adduct of said 2-hydrocarbyl-3,3-bis(4-hydroxyaryl)phthalimidine and said primary hydrocarbyl amine; (C) precipitating said adduct; and (D) decomposing said adduct to produce said 2-hydrocarbyl-3,3-bis(4-hydroxyaryl)phthalimidine.