Abstract
TpRuPPh 3 (CH 3 CN) 2 PF 6 (3 mol %) was very active in catalytic benzannulation of 1-phenyl-2-ethynylbenzenes in dichloroethane (60 °C, 36 h) to afford phenanthrene in 95% yield. This method is applicable to the synthesis of various polycyclic aromatic hydrocarbons via two- and four-fold benzannulations, including various substituted coronene derivatives (53-86% yields) using this catalyst at a moderate loading (10 mol %). © 2005 American Chemical Society.