Thermal Cyclodehydrogenations To Form 6-Membered Rings:  Cyclizations of [5]Helicenes

作者：Xiang Xue, Lawrence T. Scott · 发表于：Organic Letters · 年份：2007 · DOI：10.1021/ol7015516 · 被引用次数：52 · 研究领域：Synthesis and Properties of Aromatic Compounds、Molecular spectroscopy and chirality、Cyclization and Aryne Chemistry

Flash vacuum pyrolysis (FVP) of [5]helicene induces a thermal cyclodehydrogenation to form benzo[ghi]perylene. Evidence is presented that supports an electrocyclization-rearomatization mechanism and is inconsistent with mechanistic alternatives involving the intermediacy of aryl radicals or carbenes in the helicene fjord region.