Palladium-Catalyzed Carbonylative Synthesis of Aryl Selenoesters Using Formic Acid as an Ex Situ CO Source

Abstract

A new catalytic protocol for the synthesis of selenoesters from aryl iodides and diaryl diselenides has been developed, where formic acid was employed as an efficient, low-cost, and safe substitute for toxic and gaseous CO. This protocol presents a high functional group tolerance, providing access to a large family of selenoesters in high yields (up to 97%) while operating under mild reaction conditions, and avoids the use of selenol which is difficult to manipulate, easily oxidizes, and has a bad odor. Additionally, this method can be efficiently extended to the synthesis of thioesters with moderate-to-excellent yields, by employing for the first time diorganyl disulfides as precursors.

Recent Progress in Synthetic and Biological Application of Diorganyl Diselenides

“…In one approach, substituted arylselenoesters 114 were synthesized by employing palladium‐catalyzed carbonylative cross‐coupling of diaryl diselenides with aryl iodides (Scheme 107). [165] This reaction used formic acid as an efficient ex situ CO source. The authors studied the mechanism for the reaction and determined that the presence of zinc dust is fundamental to generating zinc selenolate, which undergoes the transmetallation reaction with palladium(II) species to give the products.…”

Synthetic Strategies for Versatile Thioester Building Blocks

“…In 2022, the Schwab group reported a mild Pd‐catalyzed reductive carbonylative thiolation of aryl iodides ( 59 ) with diaryl‐ and dialkyl disulfides ( 60 ) for synthesizing various thioesters ( 61 ), utilizing zinc as a reductant and the combination of formic acid and sulphuric acid as an ex situ CO source (Scheme 16a) [29] . Both aryl iodides and disulfides featuring electron‐donating groups performed well, as compared to the congeners with electron‐withdrawing groups.…”

Copper-Mediated Intramolecular Interrupted CuAAC Selanylation

“…In fact, the study presented here shows that this was possible by using 1,2-bis(2-azidoaryl)diselenides and alkynes (Scheme , chart E). Therefore, as part of our research program on 1,2,3-triazoles and organoselenium chemistry, we report, herein, an unprecedented domino transformation for the construction of selenium-cycle-fused 1,2,3-triazoles. This was accomplished in a straightforward fashion that includes two sequential steps in a single reaction vessel under microwave irradiation: a CuAAC reaction followed by intramolecular selanylation.…”