Selective Halogen-Lithium Exchange of 1,2-Dihaloarenes for Successive [2+4] Cycloadditions of Arynes and Isobenzofurans

Abstract

Successive [2+4] cycloadditions of arynes and isobenzofurans by site-selective halogen-lithium exchange of 1,2-dihaloarenes were developed, allowing the rapid construction of polycyclic compounds which serve as a useful synthetic intermediates for the preparation of various polyacene derivatives.

Synthesis of a Sidewall Fragment of a (12,0) Carbon Nanotube

“…Our synthetic strategy is to develop the tetraepoxy nanobelt precursor 5 with less strain, and finally generate the target CNB 6 by reductive aromatization (Scheme 1). Diels-Alder addition between the bisfuran 1 [20] and excessive in situ generated benzyne species from 2 [21] with n-BuLi [22] gave the cis-isomer 3 and trans-isomer 4 in 48 % and 32 % yield, respectively. Dibenzyne was then generated from the cis-isomer 3 with n-BuLi and the intermediate reacted with…”