Synthesis of N,N-spiro-bridged bis(cyclotriphosphazene) derivatives bearing aryl thio groups and their comparison with alkoxy and amino derivatives

Abstract

In this study, bis (1a, b) and tetrakis (2a, b) cyclotriphosphazenes containing aryl thio groups were reacted with n-butyl amine. Deprotonation reactions of the obtained mono amino bis phenylthio (3a, b) and bis naphthylthio (4a, b) cyclotriphosphazenes were carried out in the presence of NaH base. New N,N-spiro bridged biscyclotriphosphazenes containing bis geminal phenylthio (5a-I and 5a-II) and naphthythio (5b-I and 5b-II) groups were created. Characterization of the newly synthesized compounds was performed by MALDI-TOF, 31P and 1H NMR spectroscopy, and single-crystal X-Ray crystallography (5a-I and 5b-I). Photophysical properties of compounds 1a, b, 2a, b, 5a-I, and 5b-I were determined using UV/vis and fluorescence spectroscopies. At the same time, the structures of N,N-spiro bridged biscyclophosphazenes were comprehensively evaluated with the structures of previously synthesized biscyclophosphazenes containing different functional groups.