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Updated: May 25, 2026

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Evidence of enhanced conjugation in ortho-arylene ethynylenes with transition metal coordination
Qianwei Ren1, Cole G Reedy, Eric A Terrell
1Department of Chemistry, University of Wisconsin-Stevens Point, 2001 Fourth Avenue, Stevens Point, Wisconsin 54481, USA.
Abstract:
The effective conjugation of ortho and ortho-alt-para-arylene ethynylenes, with appropriately positioned pyridine and pyrazine heterocycles, increases upon binding to Ag(I) and Pd(II) cations. Significant bathochromic shifts in the electronic spectra, witnessed upon introduction of these metal bridges, are consistent with enhanced electron delocalization in the unsaturated backbone. Control studies suggest that this electronic behavior is attributable exclusively (in the case of Ag(I)) or partially (in the case of Pd(II)) to conformational restrictions of the conjugated backbones.
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