Push-pull chromophores by reaction of 2,3,5,6-tetrahalo-1,4-benzoquinones with 4-(N,N-dialkylanilino)acetylenes


Dengiz C. , PRANGE C., GAWEL P., TRAPP N., RUHLMANN L., BOUDON C., ...More

TETRAHEDRON, vol.72, no.9, pp.1213-1224, 2016 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 72 Issue: 9
  • Publication Date: 2016
  • Doi Number: 10.1016/j.tet.2016.01.017
  • Title of Journal : TETRAHEDRON
  • Page Numbers: pp.1213-1224
  • Keywords: [2+2] Cycloaddition, Fluoranil, Chloranil, Quinones, Push-pull chromophores, INTRAMOLECULAR CHARGE-TRANSFER, PHOTOINDUCED ELECTRON-TRANSFER, PORPHYRIN-QUINONE CYCLOPHANES, DONOR-ACCEPTOR SYSTEMS, DIELS-ALDER REACTION, PLANT PHOTOSYSTEM-I, TRANSFER COMPLEXES, CRYSTAL-STRUCTURE, ARTIFICIAL PHOTOSYNTHESIS, OPTOELECTRONIC PROPERTIES

Abstract

A series of new push-pull chromophores were synthesized from electron-rich 4-(N,N-dialkylanilino) acetylenes and 2,3,5,6-tetrahalo-1,4-benzoquinones. The reactivity of the latter differs substantially from that of the previously investigated 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ). The transformation with fluoranil gave orange-colored, bis-donor-substituted chromophores with a tricyclic, cyclobutene-fused dihydrobenzofuranone core. In contrast, the reaction with chioranil yielded mono donor-substituted, blue 1,4-benzoquinone-based chromophores, which were further reacted with tertiary amines to form bis-donor-substituted push-pull systems. The structures of the new chromophores were confirmed by X-ray analysis, and mechanisms for their formation are proposed. They feature intense intramolecular charge-transfer bands in the visible region, and their optoelectronic properties were investigated by UV/Vis spectroscopy, electrochemistry, and computational analysis. (C) 2016 Elsevier Ltd. All rights reserved.