Diphenic anhydride, reaction with

The reaction of diphenic anhydride with excess MDA proceeds through an imide ring opening to produce a linear polymer, or it can react with PMDA to form a cross-linked polymer (5). 

Picoline reacts with phthalic anhydride in the presence of zinc chloride or acetic anhydride to give pyrophthalone . Much work has been done on the structure of this compound . Perhaps the best formulationl is (30). Similar reactions occur with naphthalic and diphenic anhydride and in the cases of lutidines and collidines are assumed to occur at the 2-methyl group. Under similar conditions 2-picoline gives (31) with benzene-sulphonylbenzisothiazolone . 

The heterocyclic acylphosphines (52) and (53) have been prepared by the reaction of phenylbis(trimethylsilyl)phosphine with the acid chlorides derived from phthalic and diphenic acids. The reaction of 2,3-dichloromaleic anhydride or thioanhydride with phenylbis(trimethylsilyl)phosphine gives derivatives of the 1,4-dihydro-p-diphosphorin system (54).45... 

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