Disclosed herein is a method comprising reacting a phenolphthalein material and a primary hydrocarbyl amine in the presence of an acid catalyst to form a reaction mixture comprising 2-hydrocarbyl-3,3-bis(4-hydroxyaryl)phthalimidine, wherein the phenolphthalein material comprises greater than or equal to 95 weight percent phenolphthalein, based on the total weight of phenolphthalein material; quenching the reaction mixture and treating the quenched reaction mixture to obtain a first solid. The first solid is then triturated with a trituration solvent and washed to obtain a second solid, wherein the second solid comprises greater than or equal to 97 weight percent 2-hydrocarbyl-3,3-bis(4-hydroxyaryl)phthalimidine, based on the total weight of the second solid. The second solid may be polymerized to form a polycarbonate.

 
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