Palladium-Catalyzed Synthesis of 2,3-Disubstituted Benzothiophenes via the Annulation of Aryl Sulfides with Alkynes.

A new method has been developed for the synthesis of 2,3-disubstituted benzothiophenes involving the palladium-catalyzed annulation of aryl sulfides with alkynes. This convergent approach exhibited good functional group tolerance, providing rapid access to a diverse array of derivatives from simple, readily available starting materials. This protocol can also be used to synthesize 2-silyl-substituted benzothiophenes, which can be used as versatile platforms for the synthesis of 2,3-unsymmetrically substituted benzothiophenes.

Palladium(ii)-catalyzed synthesis of dibenzothiophene derivatives the cleavage of carbon-sulfur and carbon-hydrogen bonds.

A new process has been developed for the palladium(ii)-catalyzed synthesis of dibenzothiophene derivatives the cleavage of C-H and C-S bonds. In contrast to the existing methods for the synthesis of this scaffold by C-H functionalization, this new catalytic C-H/C-S coupling method does not require the presence of an external stoichiometric oxidant or reactive functionalities such as C-X or S-H, allowing its application to the synthesis of elaborate π-systems. Notably, the product-forming step of this reaction lies in an oxidative addition step rather than a reductive elimination step, making this reaction mechanistically uncommon.