Phosphorus–nitrogen compounds. Part XIX. The¹H nuclear magnetic resonance spectra of some geminal ethoxycyclotriphosphazatrienes: virtual coupling with two and three phosphorus atoms

Abstract

The 1H n.m.r. spectra of 2,2-diethoxy-4,4,6,6-tetraphenyl-, 2,2,4,4-tetraethoxy-6,6-diphenyl-, and hexaethoxycyclotriphosphazatriene have been measured at 60 and 100 Mc./sec. The methylene-proton signals of these compounds on decoupling of the methyl protons provide evidence for virtual long-range coupling with the remote phosphorus nuclei, and hence strong phosphorus–phosphorus spin–spin coupling between chemically equivalent phosphorus nuclei, in these systems. The first example of virtual coupling to three phosphorus nuclei is reported.