No proof of the constitution of the three isomeric benzene tetracarboxylic acids has apparently been offered in which they have been converted into compounds of known orientation. Numerous syntheses have made it certain that pyromellitic acid is the lI2, 4, 5- tetracarboxylic acid. Such procedures in the case of the 1, 2, 3, 4-and the 1, 2, 3, 5-acidsI however, have led to conflicting results.'The purpose of the investigation presented in this ...
