PARTICULAR INTRAMOLECULAR INTERACTION IN DIFFERENTLY P-SUBSTITUTED 2-PHOSPHINOYL (AXIAL)-1,3-DITHIANES

By X-ray structure elucidation of some of the title compounds unusual short PO-HC distances have been obtained. Concurrently, in the IR spec tra of the crystals of these substances very intense CH stretching ban ds can be detected in certain cases and, simultaneously, there are rel atively low wavenumbers of the PO stretching bands, These facts may be taken as an indication of a special molecular interaction. It is the aim of the paper to characterize this molecular interaction by vibrati onal spectroscopy. The results do not indicate the existence of a real intramolecular hydrogen bond, but they indicate a special activating interaction between the groups mentioned. (C) 1997 Elsevier Science B. V.