Samarium (III)–Modified MCM-41 Supported Ionic Liquids as Efficient Heterogeneous Catalysts toward the Fixation of CO2 into Alkynyl Carboxylic Acids

Abstract

In this work, a class of transition metal-modified MCM-41 mesoporous silica supported ionic liquids nanocatalysts were constructed and efficiently used as catalysts for the effective carboxylation of terminal alkynes through CO2 utilization. The main factors affecting the catalytic performance of carboxylation and its possible reaction mechanism were sufficiently discussed. The results showed that when the dosage was 0.2 g, the temperature was 40°C and the CO2 pressure was 0.3 MPa, the supported catalyst MCM-41@IL-Sm showed the optimal catalytic efficiency. The novel catalyst proved to be highly efficient for the sustainable synthesis of alkynyl carboxylic acids attributing good to excellent yields of 82%–95% within 7–12 h. Moreover, MCM-41@IL-Sm could be recycled and reused six times without noticeable decrease in catalytic activity from two-phase system under external heterogeneous field. The application of supported ionic liquids in the field of carbon dioxide carboxylation has injected a new power source for the efficient and effective production of value-added chemicals from waste CO2.