PUB - Publikationen an der Universität Bielefeld

According to quantum chemical calculations at an ab initio level parent 1,2-diphosphete is slightly more stable than its corresponding 1,4-diphosphabutadiene structural isomer. The quantum chemical calculations indicate that substituents at phosphorus and to a much less extent at carbon exert strong influences on the equilibrium geometries of 1,2-diphosphete structures: pi donors at phosphorus strongly elongate the P-P bond while electronegative substituents at phosphorus increase the interflap angle of the four-membered ring systems, bringing an envelope conformation to the fore. The lengthening of the P-P bond gives rise to a Mobius-type delocalization within the ring moiety.