A molecular orbital approach to conformational study of the polyisocyanates

Full Paper: A conformational study of poly(alkyl isocyanates) with both non -chiral and chiral side groups (R) is presented. For this purpose the confo rmational preferences of model compounds CH3-(CONR)(m)-CH3, where m is the number of monomers, were investigated by means of quantum mechanical method s. The influence of the number of monomers and the side chain conformation on the relative stability of the different helical minima has been systemat ically studied. Finally, the influence of the solvent chloroform has been e xamined by using a self-consistent reaction field. The results provide a de tailed structure of the modulation exerted by these factors on the helical preferences of these compounds.