A green and recyclable CuSO4•5H2O/ionic liquid catalytic system for the CO2-promoted hydration of propargyl alcohols: an efficient assembly of α-hydroxy ketones

alpha-Hydroxy ketones are important building blocks in biological, pharmaceutical and synthetic chemistry. In this work, diverse alpha-hydroxy ketones were efficiently constructed through the CO2-promoted hydration process of propargyl alcohols, which was catalyzed by a system consisted of economical CuSO4 center dot 5H(2)O and a green 1-butyl-3-methylimidazolium acetate ionic liquid. Particularly, this catalytic system exhibited excellent activity under atmospheric CO2 or even mimetic flue gas (20 vol% of CO2). Moreover, this system employed the lowest metal loading ever reported (0.004-0.25 mol%) meanwhile reached the highest turnover number (11700) for the target hydration reaction. Additionally, this is the first reported Cu catalytic system with reliable recyclability, which could be easily reused at least 6 times with yields higher than 85%. (C) 2021 Elsevier Inc. All rights reserved.

Automated summary

In this study, diverse alpha-hydroxy ketones were efficiently synthesized using an economical catalytic system. The system showed excellent activity under atmospheric CO2 or mimetic flue gas, and achieved the highest turnover number reported for the target reaction. Additionally, this is the first reported Cu catalytic system with reliable recyclability.