Acids, computational chemistry relativity

The progress of the polycondensation reaction largely depends also on the nature of the monomers, and particularly on the monomers reactivity. As a rule, electron deficient diamines will react more slowly than electron rich diamines. At this respect, some studies have been made on the reactivity of diamines by conventional methods. A reliable approach to quantify the reactivity of diamines and dianhydrides, is the calculation of molecular parameters by means of the modem methods of Computational Chemistry. The reactivity of diamines against acylating monomers like acid chlorides have been reported [29,30]. Likewise, theoretical calculations can be made to estimate the relative reactivity of diamine and dianhydride monomers. 

See S. Raugei, M. L. Klein, Journal of Physical Chemistry B 2001 105. 8212 for pertinent references to experiment, and their computational study of the formyl cation. The work shows the uncertainty associated with acid concentration, counter ion and relative O- vs-C protonation possibilities. We provide a very simplistic possibility ... 

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