Beilstein Journal of Organic Chemistry (May 2023)

Synthesis, structure, and properties of switchable cross-conjugated 1,4-diaryl-1,3-butadiynes based on 1,8-bis(dimethylamino)naphthalene

  • Semyon V. Tsybulin,
  • Ekaterina A. Filatova,
  • Alexander F. Pozharskii,
  • Valery A. Ozeryanskii,
  • Anna V. Gulevskaya

DOI
https://doi.org/10.3762/bjoc.19.49
Journal volume & issue
Vol. 19, no. 1
pp. 674 – 686

Abstract

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A set of novel 1,4-diaryl-1,3-butadiynes terminated by two 7-(arylethynyl)-1,8-bis(dimethylamino)naphthalene fragments was prepared via the Glaser–Hay oxidative dimerization of 2-ethynyl-7-(arylethynyl)-1,8-bis(dimethylamino)naphthalenes. The oligomers synthesized in this way are cross-conjugated systems, in which two conjugation pathways are possible: π-conjugation of 1,8-bis(dimethylamino)naphthalene (DMAN) fragments through a butadiyne linker and a donor–acceptor aryl–C≡C–DMAN conjugation path. The conjugation path can be “switched” simply by protonation of DMAN fragments. X-ray diffraction, UV–vis spectroscopy and cyclic voltammetry are applied to analyze the extent of π-conjugation and the efficiency of particular donor–acceptor conjugation path in these new compounds. X-ray structures and absorption spectra of doubly protonated tetrafluoroborate salts of the oligomers are also discussed.

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