Phosphorus—nitrogen compounds. Part 57 —variable‐temperature phosphorus‐31 nuclear magnetic resonance spectroscopy of some phenyl‐substituted cyclotriphosphosphazatrienes

The temperature dependence of the 31 P NMR spectra of N 3 P 3 Cl 6 , phenyl‐substituted cyclotriphosphazatrienes, N 3 P 3 Ph n Cl 6‐n ( n = 2, 4, 6), and a series of derivaties, N 3 P 3 Ph 2 [X(CH 2 ) n Y]Cl 2 (where X = Y = O, NH, n = 2, 3, 4; X = Y = NMe, n = 2, 3; X = NH, Y = NMe, n = 3), of gem ‐N 3 P 3 Ph 2 Cl 4 was studied. Differential changes in chemical shift as a function of temperature were observed between different 31 P nuclei. In a number of cases second‐order effects could be greatly reduced through a change in temperature. The temperature dependence of the 31 P shift was found to differ with solvent, for example when CDCl 3 replaced CD 2 Cl 2 .