New reactivity of 6,6-bis-donor-substituted pentafulvenes: one-step synthesis of highly substituted [3]cumulene and dihydropentalene

TETRAHEDRON

卷:71

Article

Kerisit, Nicolas¹  Finke, Aaron D.²  Trapp, Nils²  Leroux, Yann R.³  Guillernin, Jean-Claude¹  Trolez, Yann¹  Diederich, Francois² 

[1] Ecole Natl Super Chim Rennes, CNRS, UMR 6225, F-35708 Rennes 7, France

[2] ETH, Lab Organ Chem, CH-8093 Zurich, Switzerland

[3] Univ Rennes 1, Inst Sci Chim Rennes, CNRS, UMR 6226, F-35042 Rennes, France

关键词: Pentafulvenes;    [2+2] Cycloaddition;    Electrocyclization;    [3]Cumulene;    dihydropentalene;   

DOI  :  10.1016/j.tet.2015.03.081

来源: Elsevier

【 摘 要 】

We report the preparation of a 6,6-bis[(4-N,N-dimethylanilino)ethynyl]pentafulvene from a 6,6-dibromopentafulvene and 4-ethynyl-NN-dimethylaniline under Sonogashira cross-coupling conditions. A push pull [3]cumulene was formed unexpectedly during this reaction in moderate yield. The 6,6-bis [(4-N,N-dimethylanilino)ethynyl]pentafulvene was reacted with tetracyanoethylene, and an unprecedented 1,2-dihydropentalene was obtained in high yield as the exclusive product. The structures of the new compounds are supported by X-ray analysis, and a reasonable mechanism for their formation is proposed. We also report their interesting opto-electronic properties, as studied by UV/vis spectroscopy and cyclic voltammetry (CV). (C) 2015 Elsevier Ltd. All rights reserved.

【 授权许可】

Free