Three-dimensional structures of phosphorus-containing heterocycles. Communication 35. 2-Phenoxy-2-oxo-1,3,2-oxaselenaphosphorinanes

1. 2-Aroxy-2-oxo-1,3,2-oxaselenaphosphorinanes have primarily a chair conformation with an axial orientation of the aroxy grouping; the aryl group occupies a gauche orientation with respect to the P=O bond on the side of the ring O atom, The benzene ring is oriented perpendicularly to the plane of the p-O-Csp2 bonds, and this promotes disruption of the p-π conjugation. 2. The anisotropy of the polarizability of the P-Se bond and the vicinal3JpSeCH SSCC for the trans and gauche orientations of the P and H atoms were determined for the first time. © 1985 Plenum Publishing Corporation.