Computer-assisted prediction of normal boiling points of pyrans and pyrroles

Abstract

Computer-assisted methods are applied to the development of predictive models for the normal boiling points of diverse sets of pyrans and pyrroles. The models developed employ molecular structure based parameters or descriptors to encode the features of the compounds which determine the boiling point. A set of 20 descriptors is identified that allows for the development of good quality models for the pyrans and for sets of furans, tetrahydrofurans (THFs), and thiophenes, which have been studied previously. A model is presented which yields good predictions for a combined set of pyrans, furans, THFs, and thiophenes. The scope of this work is expanded to include nitrogen-containing heterocycles through the study of a diverse set of pyrroles. As part of this work, a new set of descriptors is developed for the purpose of capturing information concerning the molecular features responsible for intermolecular hydrogen-bonding interactions. Finally, the pyrrole dataset is combined with a large set of furans, THFs, thiophenes, and pyrans for the purpose of producing a more general boiling point prediction equation. The results of these studies are examined to determine their impact on future work.

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