The Synthesis, Characterization and Photophysical Properties of Some New Cyclotriphosphazene Derivatives Bearing Schiff Base

Hexa(2‐formylphenoxy)cyclotriphosphazene ( o ‐CHO‐C 6 H 4 O) 6 N 3 P 3 ( 2 ) was obtained from the reaction of hexachlorocyclotriphosphazene ( 1 ) with salicylaldehyde in the presence of K 2 CO 3 in THF solvent. A series of Schiff bases containing cyclotriphosphazenes such as [ o ‐(C 6 H 5 N=CH)C 6 H 4 O] 6 N 3 P 3 ( 3 ), [ o ‐(1‐C 10 H 7 N=CH)C 6 H 4 O] 6 N 3 P 3 ( 4 ), [ o ‐( p ‐HOC 6 H 4 N=CH)C 6 H 4 O] 6 N 3 P 3 ( 5 ), [ o ‐(2,3‐Cl 2 C 6 H 3 N=CH)C 6 H 4 O] 6 N 3 P 3 ( 6 ), [ o ‐(3,4‐Cl 2 C 6 H 3 N=CH)C 6 H 4 O] 6 N 3 P 3 ( 7 ), [ o ‐(3,5‐(CH 3 ) 2 C 6 H 3 N=CH)C 6 H 4 O] 6 N 3 P 3 ( 8 ), [ o ‐(C 6 H 5 CH 2 N=CH)C 6 H 4 O] 6 N 3 P 3 ( 9 ), [ o ‐( p ‐CH 3 OC 6 H 4 CH 2 N=CH)C 6 H 4 O] 6 N 3 P 3 ( 10 ), [ o ‐( n ‐CH 3 CH 2 CH 2 CH 2 N=CH)C 6 H 4 O] 6 N 3 P 3 ( 11 ), [ o ‐( t ‐(CH 3 ) 3 CN=CH)C 6 H 4 O] 6 N 3 P 3 ( 12 ), [ o ‐( n ‐CH 3 [CH 2 ] 10 CH 2 N=CH)C 6 H 4 O] 6 N 3 P 3 ( 13 ) were synthesized from the reaction of hexa(2‐formylphenoxy)cyclotriphosphazene ( 2 ) with aniline, 1‐naphthylamine, 2‐aminophenol, 2,3‐dichloroaniline, 3,4‐dichloroaniline, 3,5‐di‐ tert ‐butylaniline, benzylamine, p ‐methoxybenzylamine, n ‐butylamine, tert ‐butylamine and 1‐dodecylamine, respectively. The synthesized compounds were obtained in good yield and high purity. The structures of the compounds were confirmed by means of IR, NMR( 1 H, 13 C, 31 P) and elemental analysis. Photophysical properties of the cyclotriphosphazene derivates were investigated in dichloromethane solvent by UV‐Vis. spectrophotometry and spectrofluorometry (emission and excitation). Among the synthesized cyclotriphosphazene derivates, the compounds 2 , 4 , 5 , 11 and 12 exhibit emission between 390 and 550 nm at room temperature.