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Machine translation
1. (WO1980000149) PROCESS FOR PREPARING 3,4,3",4"-BENZOPHENONETETRA-CARBOXYLIC DIANHYDRIDE
Latest bibliographic data on file with the International Bureau   

Pub. No.:    WO/1980/000149    International Application No.:    PCT/US1979/000367
Publication Date: 07.02.1980 International Filing Date: 25.05.1979
IPC:
C07C 2/86 (2006.01), C07C 51/275 (2006.01), C07C 51/56 (2006.01)
Applicants:
Inventors:
Priority Data:
921571 03.07.1978 US
Title (EN) PROCESS FOR PREPARING 3,4,3",4"-BENZOPHENONETETRA-CARBOXYLIC DIANHYDRIDE
(FR) PROCEDE DE PREPARATION DE DIANHYDRIDE 3,4,3",4"-BENZOPHENONE-TETRACARBOXYLIQUE
Abstract: front page image
(EN)A process for preparing 3, 4, 3", 4"-benzophenonetetracarboxylic dianhydride which comprises condensing an impure ortho-xylene mixture with acetaldehyde in contact with an acid catalyst to obtain an impure 1,1-bis (3, 4-dimethylphenyl) ethane mixture, oxidizing the 1,1-bis (3, 4-dimethylphenyl) ethane mixture with nitric acid to obtain a mixture of carboxylic acids, from which by crystallization and dehydration substantially pure 3,4,3"4"-benzophenonetetracarboxylic dianhydride is recovered.
(FR)Un procede de preparation de dianhydride 3,4,3",4"-benzophenone-tetracarboxylique consiste a condenser un melange impur d"ortho-xylene avec de l"acetaldehyde en contact avec un catalyseur acide pour obtenir un melange impur de 1,1-bis(3,4-dimethylphenyl)ethane, a oxyder le melange de 1,1-bis(3,4-dimethylphenyl)ethane avec de l"acide nitrique pour obtenir un melange d"acides carboxyliques, a partir duquel on recupere par cristallisation et deshydratation le dianhydride 3,4,3",4"-benzophenone-tetracarboxylique sensiblement pur.
Designated States:
Publication Language: English (EN)
Filing Language: English (EN)