We prepared amide-heterocycle (HC) compounds having various aromatic π-electron systems (Ar), such as phenyl, naphthyl, furyl, thienyl and phenanthryl moieties, and converted them as ligands to difluoroboronated complexes, Ar@HCs. Blue fluorescence from Ar@HCs was observed in solution and the solid state, and the fluorescence quantum yields (Φ_f) and lifetimes (τ_f) were determined. The Φ_f values in CHCl₃ were as small as 0.1 except for the phenanthrene derivatives (0.4–0.6). Observation of the triplet–triplet absorption upon laser flash photolysis of Ar@HCs in solution indicated that the fluorescence process competes with intersystem crossing to the triplet state. Blue fluorescence in the solid state was observed with the Φ_f values of 0.3–0.7. Based on the crystallographic data, the relationship between the crystal structures and emission features of Ar@HCs in the solid state is discussed.

中文翻译：

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来自N，O配位的BF2配合物的蓝色荧光，该配合物在溶液和固态下均具有芳香族发色团。

我们制备了具有各种芳族π电子系统（Ar）（例如苯基，萘基，呋喃基，噻吩基和菲基部分）的酰胺-杂环（HC）化合物，并将它们作为配体转化为二氟硼化配合物Ar @ HCs。在溶液和固体状态中观察到选自Ar蓝色荧光@的HC，荧光量子产率（Φ _˚F）和寿命（τ _˚F）进行了测定。的Φ _˚F在CHCl值₃除菲衍生物（0.4–0.6）外，其他元素均小至0.1。对溶液中Ar @ HCs进行激光快速光解后的三重态-三重态吸收观察表明，荧光过程与系统间交叉竞争为三重态。在固体状态下的蓝色荧光与所观察到Φ _˚F的0.3-0.7值。基于晶体学数据，研究了固态Ar @ HCs的晶体结构与发射特征之间的关系。