Skip to Main content Skip to Navigation
Journal articles

1,3,2-benzodiazaboroles with 1,3-pentafluorophenyl and tetrafluoropyridyl substituents as building blocks in luminescent compounds

Abstract : The reaction of N-4′-trimethylsilylphenyl-3,6-di-tert-butylcarbazole (3) or N-5′-trimethylsilylthien-2′-yl-3,6-di-tert-butylcarbazole (4) with boron tribromide and subsequently with triphenylphosphane afforded the dibromoborylphenylcarbazole-phosphane adduct 5 or its thiophene derivative 6 as colorless solids. These adducts were converted into the new benzodiazaborole derivatives 7 and 8 by treatment with N,N′-bis(pentafluorophenyl)-o- phenylenediamine (1) and 2,2,6,6-tetramethylpiperidine in hot toluene (52 or 45 % yield). The analogous compounds 9 and 10 were obtained by condensing precursors 5 and 6 with bis(N,N′-2,3,5,6-tetrafluoropyrid-4-yl)-o- phenylenediamine (2) in the presence of the piperidine derivative in 35 and 16 % yield. Compounds 7-10 were characterized by NMR spectroscopy (1H, 11B, 13C, 19F) and mass spectrometry. The molecular structure of 8 was elucidated by X-ray diffraction analysis. The borylated systems show intense blue luminescence upon UV irradiation. In contrast to π-donating 1,3-diethyl- and 1,3-diphenyl-1,3,2-benzodiazaboroles, derivatives with fluoroaryl substituents at the ring nitrogen atoms are potent π acceptors when connected to a carbazole donor through suitable π-conducting spacers. Thus, molecules of type A show low-energy emission bands from charge-transfer (CT) transitions with large Stokes shifts and pronounced solvatochromism.
Complete list of metadata

https://hal.archives-ouvertes.fr/hal-01549705
Contributor : Sylvie Blanc <>
Submitted on : Thursday, June 29, 2017 - 9:45:54 AM
Last modification on : Thursday, February 18, 2021 - 3:24:26 AM

Links full text

Identifiers

Collections

Citation

L. Weber, J. Halama, L. Böhling, A. Brockhinke, Anna Chrostowska, et al.. 1,3,2-benzodiazaboroles with 1,3-pentafluorophenyl and tetrafluoropyridyl substituents as building blocks in luminescent compounds. European Journal of Inorganic Chemistry, Wiley-VCH Verlag, 2013, pp.4268-4279. ⟨10.1002/ejic.201300319⟩. ⟨hal-01549705⟩

Share

Metrics

Record views

189