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The new hexasubstitue-cyclophosphazene compounds containing chalcone derivatives (2-11) were obtained from the reactions of hexachlorocyclotriphosphazene (1) with several hydroxy chalcones in K 2 CO 3 /acetone system. All products were generally obtained in high yields. The structures of the compounds were defined by elemental analysis, FT-IR, 1 H, 13 C and 31 P NMR spectroscopy. Dielectric measurements for phosphazenes containing chalcone compounds (5-8) were carried out by means of an impedance analyzer as a function of temperature and frequency. Dielectric properties of samples prepared in a plate form were measured at room temperature over the frequency range 50 Hz to 2 kHz and given as compared with each other.

The cyclotriphosphazene compound (2) bearing formyl groups as side groups was obtained from the reaction of 2,2-Dichloro-4,4,6,6-bis[spiro(2 0 ,2 00 -dioxy-1 0 ,1 00 -biphenylyl)]cyclotriphosphazene (1) with 4hydroxy-3-methoxybenzaldehyde in the presence K 2 CO 3 in tetrahydrofuran. Oxime-cyclotri phosphazene compound (3) was synthesized from the reaction of compound 2 with hydroxylamine hydrochloride in pyridine. The synthesized oxime-phosphazene compound (3) was reacted with alkyl and acyl halides. As a results, the cyclotriphosphazene compounds (1e10) bearing oxime ether and ester as side groups were obtained. The chemical structures of these compounds (1e10) were determined by elemental analysis, FT-IR, 1 H, 13 C and 31 P NMR spectroscopic methods. Dielectric constant, dielectric loss factors and conductivity properties of cyclotriphosphazene compounds were measured over the frequency range from 100 Hz to 2 kHz at 25 C and compared with each other. It is found that ester substituted cyclotriphosphazenes have higher dielectric constant. Our study suggests that these phosphazenes promising candidate materials in multifunctional optoelectronic devices.

Hexachlorocylotriphosphazene (1) was reacted with 4-hydroxy-3-methoxybenzaldehyde to give hexakis[(4-formyl-2-methoxy)phenoxy]cyclotriphosphazene (2). Hexakis[(4-(hydroxyimino)2-methoxy)phenoxy]cyclotriphosphazene (3) was synthesized by reaction of 2 with hydroxlamine hydrochloride in pyridine. Compound 3 was reacted with benzyl chloride, acetyl chloride, allyl bromide, benzoyl chloride, propanoyl chloride, 4-methoxybenzoyl chloride, 2-chlorobenzoyl chloride, chloroacetyl chloride, methyl iodide, and thiophene-2-carbonyl chloride. From these reactions, full or partially substituted compounds were obtained, usually in high yields. Pure or defined products could not be obtained from reaction of 3 with methacryloyl chloride and O-acetylsalicyloyl chloride. The structures of the compounds were determined by elemental analysis, and IR, 1 H, 13 C, and 31 P NMR spectroscopy. The synthesized compounds were screened for in-vitro antimicrobial activity against two Gram-positive bacteria (Staphylococcus aureus and Enterococcus faecalis), two gram-negative bacteria (Escherichia coli and Klebsiella pneumonia), and fungal strains (Aspergillus niger, and Candida albicans) by the agar well diffusion method. Few compounds had significant activity against both Grampositive and Gram-negative bacteria. None of the compounds had antifungal activity except compounds 7 and 9, which had moderate activity.

A series of new cyclotriphosphazene derivatives (2a-e) were prepared from the reactions of substituted chalcone compounds (1a-e) containing different organic side groups at para position with cyclotriphosphazene (2) bearing dioxybiphenyl. The structures of 2a-e were approved by microanalysis and spectroscopic techniques (MS, FT-IR, 31 P, 1 H, 13 C, and 13 C-APT NMR). The thermal behaviors of compounds 2a-e were investigated by thermogravimetric analysis (TGA). These compounds were found to be stable up to about 300°C. Dielectric properties of 2a-e were measured against temperature (between 25 and 160°C at 1 kHz) and frequency (range from 100 Hz to 5 kHz at 25°C) using means of an impedance analyzer. Among them dielectric properties of methoxy substituted cyclotriphosphazene 2e were found to be higher than other phosphazenes. The compound 2b, which has the lower dielectric property values than other phosphazenes, was selected to determine the influence of Eu +3-doping on the dielectric properties of phosphazenes and doped with Eu +3 at different mole ratios. At the dielectric properties of Eu +3-doped compound 2b (with increasing molar ratios of Eu +3) was observed an excellent increasing according to Eu +3-undoped phosphazene compounds.

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