Highly Substituted Acephenanthrylenes and Their π-Extended Derivatives: Syntheses, Structural Analyses, and Properties

Org Lett. 2022 Jul 8;24(26):4778-4782. doi: 10.1021/acs.orglett.2c01778. Epub 2022 Jun 23.

Abstract

This investigation demonstrates that a series of (highly) substituted acephenanthrylenes (APs) 2, benzo[l]acephenanthrylene 3, and dicyclopenta[cd,mn]pyrene 4 are easily prepared by palladium-catalyzed cycloaromatization of 2,3-diethynylbiphenyls 1. The first nonpyrolysis synthesis of 4 by two-fold cycloaromatization was achieved in a high yield. This synthetic protocol has two crucial advantages: facile introduction of various substituents and efficient extension of the AP backbone.