Synthesis of Cyano‐Substituted Diaryltetracenes from Tetraaryl[3]cumulenes

• DOI: 10.1002/anie.201402299
• Publication Date: 2014-03-25T02:17:30Z
• Authors: Przemyslaw Gawel; Cagatay Dengiz; Aaron D. Finke; Nils Trapp; Corinne Boudon; Jean‐Paul Gisselb...; François Diederich
• Keywords: Tetracyanoethylene; Zwitterion; Chromophore; Aromatization

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 tetracyanoethylene (TCNE) to the proacetylenic central double bond cumulenes give an intermediate zwitterion, which after electrocyclization cascade and dehydrogenation yields 5,5,11,11-tetracyano-5,11-dihydrotetracenes in a one-pot procedure. subsequent copper-assisted decyanation/aromatization provided target 5,11-dicyano-6,12-diaryltetracene derivatives. All postulated structures were confirmed X-ray crystallography. The new chromophores are thermally stable feature promising fluorescence properties for potential use optoelectronic devices. They selective chemosensors Cu(I) ions, coordinate one CN substituents form 1:1 complex with association constant Ka =1.5×10(5) L mol(-1) at 298 K.