Synthesis of Cyano-Substituted Diaryltetracenes from Tetraaryl[3] cumulenes**

GAWEL P., Dengiz C., FINKE A. D., TRAPP N., BOUDON C., GISSELBRECHT J., ...More

ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, vol.53, no.17, pp.4341-4345, 2014 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 53 Issue: 17
  • Publication Date: 2014
  • Doi Number: 10.1002/anie.201402299
  • Journal Name: ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.4341-4345
  • Keywords: [2+2] cycloaddition, [3]cumulenes, chemosensors, electrocyclization, tetracenes, CHARGE-TRANSFER, CHROMOPHORES, BUTATRIENE, CONSTRUCTION, RADIALENES, CRUCIFORMS, TRANSPORT
  • Middle East Technical University Affiliated: No

Abstract

A versatile, two-step synthesis of highly substituted, cyano-functionalized diaryltetracenes has been developed, starting from easily accessible tetraaryl[3]cumulenes. This unprecedented transformation is initiated by [2+2] cycloaddition of tetracyanoethylene (TCNE) to the proacetylenic central double bond of the cumulenes to give an intermediate zwitterion, which after an electrocyclization cascade and dehydrogenation yields 5,5,11,11-tetracyano-5,11-dihydrotetracenes in a one-pot procedure. A subsequent copper-assisted decyanation/aromatization provided the target 5,11-dicyano-6,12-diaryltetracene derivatives. All of the postulated structures were confirmed by X-ray crystallography. The new chromophores are thermally highly stable and feature promising fluorescence properties for potential use in optoelectronic devices. They are selective chemosensors for Cu-I ions, which coordinate to one of the CN substituents and form a 1:1 complex with an association constant of K-a=1.5x10(5)Lmol(-1) at 298K.