Abstract In this study, three novel oxy-naphthylchalcone appended cyclotriphosphazene derivatives (3, 4 and 5) were obtained by the nucleophilic substitution reactions of cyclotriphosphazene cores (1, 1a and 1b) with (E)-3-(4-hydroxyphenyl)-1-(naphthalene-2-yl) prop-2-en-1-one (2) in presence of K2CO3/acetone. Novel compounds 3, 4 and 5 were characterized with using NMR (1H and 31P), elemental analysis, mass and FT-IR spectroscopies. In addition, molecular and crystal structures of 2 and 3 were determined by single crystal X-ray crystallography. The photophysical and intramolecular energy transfer properties of novel oxy-naphthylchalcone appended cyclotriphosphazene derivatives (3, 4 and 5) and their precursors (1a and 1b) were examined by steady state-/time resolved fluorescence spectroscopy, UV–Vis absorption spectroscopy and excitation-emission matrix (EEM) analysis. According to obtained results, novel target compounds (4 and 5) demonstrate a highly efficient intramolecular fluorescence resonance energy transfer (FRET) between excited phenol/naphthol groups and oxy-naphthylchalcone group.

中文翻译：

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氧萘查尔酮附加环三磷腈核的合成、表征、光物理和分子内能量转移特性

摘要 在本研究中，通过环三磷腈核心（1、1a 和 1b）与（E）-3-（4-羟基苯基）-的亲核取代反应，获得了三种新型的氧-萘基查尔酮附加环三磷腈衍生物（3、4 和 5）。 1-(naphthalene-2-yl) prop-2-en-1-one (2) 在 K2CO3/丙酮存在下。新化合物 3、4 和 5 使用 NMR（1H 和 31P）、元素分析、质谱和 FT-IR 光谱进行了表征。此外，2 和 3 的分子和晶体结构是通过单晶 X 射线晶体学确定的。通过稳态/时间分辨荧光光谱检查了新型氧-萘基查尔酮附加环三磷腈衍生物（3、4和5）及其前体（1a和1b）的光物理和分子内能量转移特性，紫外-可见吸收光谱和激发-发射矩阵 (EEM) 分析。根据获得的结果，新的目标化合物（4 和 5）证明了激发的苯酚/萘酚基团和氧萘基查尔酮基团之间的高效分子内荧光共振能量转移（FRET）。