Synthesis and characterization of novel urea and thiourea substitute cyclotriphosphazene compounds as naked-eye sensors for F$^{-}$ and CN$^{-}$ anions

Abstract

Novel hexakisurea and thiourea cyclotriphosphazene compounds (3-7) were synthesized. The structure of all compounds was identified using FT-IR 1 H, 13 C, and 31 P NMR spectroscopy; MALDI-TOF MS; and elemental analysis. The optical sensor properties for anions of 3-7 were investigated using UV-Vis spectroscopy. It was determined that compounds 6 and 7 are spectrophotometric and naked eye sensors for F − and CN − anions, respectively. Sensor properties of these compounds for anions were investigated using UV-Vis spectroscopy. The stoichiometry of host-guest complexes was found to be 1:6.

Curing of Epoxy Resin DER-331 by Hexakis(4-acetamidophenoxy)cyclotriphosphazene and Properties of the Prepared Composition

“…Hexakis(4-acetamidophenoxy)cyclotriphosphazene (ACP) is the most actively explored among phosphazene derivatives, since its synthesis is fairly simple [25,26,27,28]. This compound may be of significant interest as a hardener of industrial epoxy resins for the production of non-combustible materials based on them.…”

Calix[4]pyrroles with bulky substituents and their anion binding studies

“…Mp: decomposes over 210 • C; 1 H NMR (250 MHz, CDCl 3 ) δ (ppm) = 1.67 (br m, 16H, CH 2 ), 1.88 (br m, 8H, CH 2 ) , 2.28 (br m, 8H, CH 2 ), 2.60 (br, 4H, CH), 5.81-6.19 (m, 8H, pyrrole-CH), 6.87 (2H, NH), 6.97-7.14 (br m, 20H, phenyl CH), 7.30 (2H, NH). 13…”

“…12 However, the weak nature of the anionreceptor interactions, reflecting the relatively low charge density of most anions, prompted researchers to design sophisticated anion receptor systems to achieve better control of recognition and selectivity. While many reported anion receptors have proven to be quite effective, 13,14 calix [4]pyrroles (1 and 2 in Figure 1) have become some of the anion receptors that are easiest to make. 15,16 This is because the core and functional structures can be accessed in one synthetic step and a large number of modifications are readily conceivable.…”

“…). Mp: 182-184 • C; 1 H NMR CH), 5.95 (4H, pyrrole CH),6.98 (2H, NH), 7.15-7.27 (br m, 20H, phenyl CH and NH) 13. C NMR (60 MHz, CDCl 3 ): 30.28, 37.29, 37.86, 39.04, 39.38, 43,97, 101.27, 126.02, 126.70, 127.76, 128.32, 128.82, 132.19, 133.24, 140.51, 147.05 ppm.…”