Crystal Structure and Excimer Fluorescence of Some Benzoylacetonatoboron Difluorides: Stacking Factor

The comparative study of the crystal structures of benzoylacetonato- (1), p-toluylacetonato- (2) and p-ethylbenzoylacetonatoboron (3) difluoride was carried out. Correlation of the luminescence properties of the complexes 1–3 and their crystal structures was revealed. The excimer formation in these compounds occurred the most efficiently for the complexes 1 characterized by the formation of stacks of molecules, unlike the complex 3, where individual dimers behaved as excimer-forming centers. The maximal fluorescence intensity was observed for the complex 2, which had the highest structural ordering.     

Boron Difluoride β-Diketonates: IV. Reaction of p-Alkyl-substituted Benzoylacetonates with N-Bromosuccinimide

Bromination of p-alkyl-substituted boron difluoride and chromium(III) benzoylacetonates with N-bromosuccinimide was studied. It was found that that the boron difluoride complexes are selectively brominated by the alkyl radical, whereas chromium toluoylacetonate, by the central carbon atom of the chelate ring.     

Crystal structure and fluorescence properties of p-nitrobenzoylanisoylmethane and its complex with boron difluoride

The crystal and molecular structures of p- and m-nitrobenzoylanisoylmethanatoboron difluoride were determined. The spectral luminescence properties of these compounds were studied and compared.     

Boron Difluoride β-Diketonates: III. Boron Difluoride 3-Organylpenta-2,4-dionates

Boron difluoride 3-methyl-, 3-ethyl-, 3-propyl-, 3-isopropyl-, and 3-phenylacetylacetonates were synthesized by acylation of ketones with acetic anhydride, chelation of -organyl--diketones, and reaction of acetylacetone with isopropanol in the presence of boron trifluoride. The resulting chelates were characterized by ¹H NMR, IR, and UV spectroscopy.     

Fluorescence and photochemical properties of crystalline boron difluorides β-diketonato

The fluorescence and photochemical properties of crystalline β-diketonatoboron difluorides (DBD) RCOCHCOR¹BF₂ were studied. These compounds are characterized by relatively high photochemical stability. The introduction of electron-donating groups into the aromatic α-substituent of the chelate ring increases and the introduction of electron-withdrawing groups decreases the fluorescence intensity of DBD. Anisoylbenzoylmethanotoboron difluoride was found to exhibit the highest fluorescence intensity. The substituents were shown to influence the relative arrangement of singlet and triplet ηπ^* and ππ^* levels and luminescence properties of compounds. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1030–1033, June, 2000.     

Crystal structure and excimer fluorescence of dibenzoylmethanatoboron difluoride

Fluorescence properties of dilute and concentrated solutions of dibenzoylmethanatoboron difluoride and its crystals were studied. Excimers are formed in concentrated solutions and crystals of dibenzoylmethanatoboron difluoride. The crystal structure of dibenzoylmethanatoboron difluoride was determined by X-ray diffraction analysis. It was found that the molecules of dibenzoylmethanatoboron difluoride are coplanar with an interplanar distance of 3.6 .     

Crystal Structure and Luminescence of Boron Difluoride Acetylacetonate

The structure of boron difluoride acetylacetonate was studied by X-ray diffraction. A pucker of the chelate ring along the line connecting the boron and -carbon atom was detected. The effects of geometric and electronic factors on the fluorescence intensity of boron difluoride -diketonates were discussed.