Unexpected rate retardation in the formation of phthalic anhydride from N-Methylphthalamic Acid in acidic H2O-CH3CN medium

Ariffin, A. and Khan, M.N. (2005) Unexpected rate retardation in the formation of phthalic anhydride from N-Methylphthalamic Acid in acidic H2O-CH3CN medium. Bulletin of the Korean Chemical Society, 26 (7). pp. 1037-1043. ISSN 0253-2964

Full text not available from this repository. (Request a copy)
Official URL: http://koreascience.or.kr/article/ArticleFullRecor...

Abstract

Kinetic study on the cleavage of N-methylphthalamic acid (NMPA) in mixed acidic aqueous-acetonitrile solvent reveals the formation of both phthalic anhydride (PAn) (through O-cyclization) and N-methylphthalimide (NMPT) (through N-cyclization). The formation of NMPT varies from similar to 20% to similar to 3% with the increase in the content of acetonitrile from 2 to 70% v/v. Pseudo first-order rate constants for the formation of PAn are more than 4-fold larger than those for the formation of NMPT at 2% v/v CH3CN in mixed aqueous solvents. Pseudo first-order rate constants for alkaline hydrolysis of NMPT reveal a nonlinear decrease with increase in the content of CH3CN in mixed aqueous solvents.

Item Type: Article
Additional Information: Department of Chemistry, Faculty of Science Building, University of Malaya, 50603 Kuala Lumpur, MALAYSIA
Uncontrolled Keywords: phthalic anhydride, kinetics, hydrolysis, o-cyclization and n-cyclization of n-methylphthalamic acid, intramolecular catalysis, amide hydrolysis, alkaline-hydrolysis, aqueous cleavage, imide formation, mechanism, kinetics, cyclization, hydroxyphthalimide, participation
Subjects: Q Science > QD Chemistry
Divisions: Faculty of Science > Dept of Chemistry
Depositing User: Miss Malisa Diana
Date Deposited: 03 Jul 2013 09:06
Last Modified: 03 Jul 2013 09:06
URI: http://eprints.um.edu.my/id/eprint/8044

Actions (login required)

View Item View Item