Synthesis and structures of unsymmetrical bis- and tris-cyclotriphosphazenes

Single Molecular Persistent Room-Temperature Phosphorescence and Circularly Polarized Luminescence from Binaphthol-Decorated Optically Innocent Cyclotriphosphazenes

Circularly polarized luminescence (CPL) features of BINOL-decorated cyclotriphosphazenes (CPs) are reported for the first time. The luminescence dissymmetry factor (glum ) of these compounds in chloroform solutions and polymethyl methacrylate (PMMA) thin films with wt 1 % doping concentrations are found to be 1.0×10-3 , and 2.9×10-3 , respectively. However, no CPL signal is observed for the pristine solids. The enantiomers (CP-(R)/CP-(S)) show ultraviolet photoluminescence (~350-360 nm) in solution and the solid state. These compounds show ~10 times larger absolute photoluminescence quantum yield (PLQY) than the simple BINOLs in the solutions state. In the solid state, CP-(R) shows larger PLQY than binaphthol-(R); in contrast, the S enantiomer shows lower PLQY than binaphthol-(S); this indicates that the isomer-dependent solid-state packing of these compounds plays a crucial role in controlling the PL. Thin films with more than 1 % doping concentration and pristine solids of these compounds do not show persistent room-temperature phosphorescence (pRTP) due to concentration-caused quenching. However, thin films with wt 1 % of these chiral emitters exhibit pRTP characteristics with a ~159-343 ms lifetime under vacuum. Theoretical calculations reveal that the cyclophosphazene acts as an optically innocent dendritic core, and the optical features of these compounds are dictated by the pendent BINOL chromophore.

Synthesis, characterization, and photophysical and fluorescence sensor behaviors of a new water-soluble double-bridged naphthalene diimide appended cyclotriphosphazene

A new water-soluble template of double-bridged naphthalene diimide appended cyclotriphosphazene was prepared, and its photophysical and sensor behaviors were evaluated. The characterization of novel double-bridged naphthalene diimide appended cyclotriphosphazene (6) was carried out by NMR (1H, 13C, 31P) and mass spectroscopies. The photophysical behaviors of compound 6 were evaluated by UV-Vis absorption and fluorescence spectroscopies in various solvent systems and different concentrations. As an application for usability of the obtained water-soluble template in different applications, the fluorescence sensor property of compound 6 was investigated in the presence of many different competing species (organic acids, saccharides, nitroaromatic compounds, anions, and metal cations). The results obtained showed that compound 6 had selectivity against only the nitroaromatic species among the competing species tested.

Phosphorus-nitrogen compounds. Part 23: syntheses, structural investigations, biological activities, and DNA interactions of new N/O spirocyclotriphosphazenes

The Schiff base compounds (1 and 2) are synthesized by the condensation reactions of 2-furan-2-yl-methylamine with 2-hydroxy-3-methoxy- and 2-hydroxy-5-methoxy-benzaldehydes and reduced with NaBH(4) to give the new N/O-donor-type ligands (3 and 4). The monospirocyclotriphosphazenes containing 1,3,2-oxazaphosphorine rings (5 and 6) are prepared from the reactions of N(3)P(3)Cl(6) with 3 and 4, respectively. The reactions of 5 and 6 with excess pyrrolidine, morpholine, and 1,4-dioxa-8-azaspiro [4,5] decane (DASD) produce tetrapyrrolidino (5a and 6a), morpholino (5b and 6b), and 1,4-dioxa-8-azaspiro [4,5] deca (5c and 6c) spirocyclotriphosphazenes. The structural investigations of the compounds are examined by (1)H, (13)C, (31)P NMR, DEPT, HSQC, and HMBC techniques. The solid-state structures of 5, 5a, and 6 are determined using X-ray crystallography. The compounds 5a, 5b, 5c, 6a, 6b, and 6c are subjected to antimicrobial activity against six patojen bacteria and two yeast strains. In addition, interactions between these compounds and pBR322 plasmid DNA are presented by agarose gel electrophoresis.

Structural and fluorescence properties of phenolphthalein bridged cyclotriphosphazatrienes

This study dealt with the reactions of hexachlorocyclotriphosphazatriene, N(3)P(3)Cl(6) (trimer) (1) with phenolphthalein (2) to give the phenolphthalein bridged compounds 3, 4 and 5. The phenolphthalein bridged cyclotriphosphazatriene derivatives are reported for the first time. The new compounds (3-5) are characterized by elemental analysis, mass spectrometry, UV-vis, FT-IR, (1)H, (31)P NMR and fluorescence spectroscopy. The more bridged phenolphthalein groups show the higher intensity of the absorption bands in the UV-vis spectra. Fluorescence spectrum of compound 3 shows a small band in the lower spectral range, while the spectra of compounds 4 and 5 show more intense and a band in higher spectral range.