Methods for purifying 2-aryl-3,3-bis(hydroxyaryl)phthalimidines

US7790832B2 · kind B2 · utility

Assignee

• Sabic Innovative Plastics B.V. · NL

Inventors

• Balakrishnan Ganesan · Bengaluru, IN
• Pradeep Nadkarni · Bengaluru, IN
• Kumar Arun Satyanarayana · Bengaluru, IN
• Venkata Rama Narayanan Ganapathy Bhotla · Bengaluru, IN
• Suresh Shanumgam · Bengaluru, IN
• Gurram Kishan · Bengaluru, IN
• Ravindra Vikram Singh · Sidhauli, IN

Key dates

• Filing date: Sep 4, 2007
• Grant date: Sep 7, 2010
• Expiry date: Sep 4, 2027

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G64/12
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A method for purifying a 2-aryl-3,3-bis(hydroxyaryl)phthalimidine comprises contacting a crude 2-aryl-3,3-bis(hydroxyaryl)phthalimidine with a purification agent, removing a 2-aryl-3-(aminoaryl)-3-(hydroxyaryl)phthalimidine compound from the crude 2-aryl-3,3-bis(hydroxyaryl)phthalimidine, and producing a purified 2-aryl-3,3-bis(hydroxyaryl)phthalimidine product comprising less than 200 parts per million of the 2-aryl-3-(aminoaryl)-3-(hydroxyaryl)phthalimidine compound. The purification agent is selected from the group consisting of an acidic material, an organic acid chloride, an organic anhydride, or a combination thereof. The 2-aryl-3-(aminoaryl)-3-(hydroxyaryl)phthalimidine compound has a formula:wherein each R1 is independently selected from a group consisting of a hydrocarbyl radical, a nitro radical, and a halogen atom; “a” is an integer from 0 to 4; and Ar1 and Ar2 are independently at each occurrence an aromatic radical. The purified 2-aryl-3,3-bis(hydroxyaryl)phthalimidines have low color, and are useful for preparing polymers, such as polycarbonates having a low color. The polycarbonates are useful for producing articles.