Glicerol como Solvente Reciclável em Reações de Acoplamento entre Disselenetos de Diarila com Ácidos Arilborônicos

Abstract

In this work, we describe the use of glycerol as solvent in the cross-coupling reaction of diaryl diselenides 1 with arylboronic acids 2 using a catalytic amount of CuI and DMSO as additive at 110 °C under air atmosp here. This is a general crosscoupling reaction and was performed with diaryl diselenides and arylboronic acids bearing electron-withdrawing and electron-donating groups, affording the corresponding diaryl selenides 3 in good to excellent yields. After that, under the optimized reaction conditions, the possibility of performing the reaction with other diphenyl dichalcogenides was also investigated. 4- Methoxyphenylboronic acid 2a was efficiently reacted with diphenyl ditelluride, affording the respective diaryltelluride 4 in excellent yield. However, when the reaction of arylboronic acid 2a was performed with diphenyl disulfide, low yield of diarylsufide 5 was obtained. Additionally, a study regarding the recovering and reusing of glycerol was performed. In the reaction of diphenyl diselenide 1a with arylboronic acid 2a under the optimized reaction conditions, after the consumption of starting materials, the reaction was extracted and the remaining CuI/glycerol mixture was directly reused for further reactions. It was observed that a good level of efficiency was maintained even after being reused four times. The product 3a was obtained in high yields after successive cycles wich, is particularly appropriate to the green chemistry concept.