Thermodynamically Stable o-Quinodimethane: Synthesis, Structure, and Reactivity

Kazuhiko Adachi; Shunsuke Hirose; Yasuyuki Ueda; Hidehiro Uekusa; Toshiyuki Hamura

doi:10.1002/chem.202004510

Thermodynamically Stable o-Quinodimethane: Synthesis, Structure, and Reactivity

Chemistry. 2021 Feb 19;27(11):3665-3669. doi: 10.1002/chem.202004510. Epub 2020 Dec 1.

Authors

Kazuhiko Adachi¹, Shunsuke Hirose¹, Yasuyuki Ueda¹, Hidehiro Uekusa², Toshiyuki Hamura¹

Affiliations

¹ Department of Applied Chemistry for Environment, Kwansei Gakuin University, 2-1 Gakuen, Sanda, 669-1337, Japan.
² Department of Chemistry, School of Science, Tokyo Institute of Technology, Ookayama 2, Meguro-ku, Tokyo, 152-8551, Japan.

PMID: 33159368
DOI: 10.1002/chem.202004510

Abstract

Thermal isomerization of cyclobutaphenanthrene to o-quinodimethane was investigated. Sterically congested substituents or electron-donating substituents on the four-membered ring promoted the ring-opening, affording o-quinodimethane in a relatively stable form. Isolation of the newly prepared o-quinodimethane allowed its structural elucidation and investigation of its potential reactivities. Dual [4+2] cycloaddition of an aryne and o-quinodimethane afforded tetrabenzopentacene, demonstrating the synthetic application of the isolated compound.

Keywords: aryne; cycloaddition; cyclobutaarenes; polycyclic aromatic hydrocarbon; quinodimethanes.