Studies of phosphazenes. Part 25. Synthesis, nuclear magnetic resonance spectroscopy, and mode of formation of (aziridino)(triphenylphosphazenyl)cyclotriphosphazenes. X-Ray crystal structure and enzyme-inhibiting activity of N < inf > 3 < /inf > P < inf > 3 < /inf > (NPPh < inf > 3 < /inf > )(NC < inf > 2 < /inf > H < inf > 4 < /inf > ) < inf > 5 < /inf >

Abstract

Aziridino (HNC2H4) reacts with the triphenylphosphazenyl derivative N3P3(NPPh3)Cl5 (1) to yield the compounds N3P3(NPPh3)(NC2H4) nCl5-n [n = 1-5; (3)-(9)], the structures of which are elucidated by 1H and 31P n.m.r. spectroscopy. The fluoro-analogue, N3P3(NPPh3)F5 (2), is unreactive even under drastic conditions. The chlorine replacement pattern and the associated mechanistic aspects are discussed. The X-ray crystal structure analysis of N3P3(NPPh3)(NC2H4) 5 (9) shows a novel conformation of the -NPPh3 substituent in which one of the phenyl groups lies in a plane nearly perpendicular and in close proximity to the -NC2H4 group at the ≡P(NPPh3)(NC2H4) site. The n.m.r. [1H, 13C, and 31P] parameters of (9) are discussed in relation to its structure. The enzyme-inhibiting activity of (9) is compared with that of N3P3(NC2H4)6.