Aromatization of cyclic hydrocarbons via thioether elimination reaction

Meta-Selective Copper-Catalyzed C-H Arylation of Pyridines and Isoquinolines through Dearomatized Intermediates

C(sp2)-H functionalization offers an efficient strategy for the synthesis of various elaborated N-containing heteroarenes. Along these lines, oxazino pyridines that can be readily prepared from pyridines, have been introduced as powerful substrates in radical- and ionic-mediated meta-C-H functionalization. However, the regioselective meta-C-H arylation of pyridines remains a great challenge. Herein, a copper-catalyzed meta-selective C-H arylation of pyridines and isoquinolines through bench-stable dearomatized intermediates is reported. Electrophilic aryl-Cu(III) species, generated from readily accessible aryl I(III) reagents, enable the efficient meta-arylation of a broad range of pyridines and isoquinolines. The method also allows the meta-selective alkenylation of these heteroarenes using the corresponding alkenyl I(III)-reagents. Late-stage arylation of drug-derived pyridines and larger-scale experiments demonstrate the potential of this synthetic methodology.

Potassium xanthate-promoted reductive sulfuration reaction: from aldehydes to thiol, disulfide, and thioester derivatives

Herein, we developed a synthetic strategy for the direct construction of C-S bonds to obtain biologically active sulfur-containing compounds and a methodology involving the reductive sulfuration of aldehydes or ketones to obtain diverse substituted thiol, disulfide, and thioester derivatives. EtOCS2K is demonstrated as a potential substitute for the Berzelius reagent or Lawesson's reagent for the construction of C-S bonds.