Straightforward Synthesis of Novel Acene-Based Aryne Precursors
Large polycyclic o-(trimethylsilyl)aryl triflates are easily obtained by reaction of commercially available bisaryne precursors with cyclopentadienones. The transformation involves controlled generation of one of the aryne functionalities, trapping by Diels–Alder reaction with a dienone, and chelotropic extrusion of CO. The newly synthesized triflates are precursors of acene-based arynes, including a didehydropentacene ; Financial support from the Spanish Ministry of Science and Competitiveness (MINECO, CTQ2013-44142-P and MAT2013-46593-C6-6-P), the European Union (Project PAMS, contract no. 610446), Xunta de Galicia (GPC2014/25), and FEDER is gratefully acknowledged. D.R.-L. thanks the Spanish Ministry of Education for the award of an FPU fellowship ; SI