Direct synthesis of cyclic carbonates from olefins and CO2: Single- or multi-component catalytic systems via epoxide or halohydrin intermediate

Single-component or multi-component catalytic systems were discussed for direct synthesis of cyclic carbonates from olefins and CO 2 . And the halohydrins or epoxides as the intermediates in their corresponding mechanisms were presented to give hints to develop single component multifunctional catalysts or developing new transformation strategies. • Single or multi-component catalytic systems for direct synthesis of cyclic carbonates from olefins/CO 2 were discussed. • Discussed systems were further divided into transition metal and transition-metal-free ones. • Noble and non-noble metals combined some quaternary ammonium salts and so on constituted transition metal systems. • Mechanisms involving the halohydrins or epoxides as the intermediates were elaborated. With dramatical rise of carbon dioxide emission leading to greenhouse effect and CO 2 as an important renewable C1 source, converting CO 2 to high value-added chemicals is urgent. Cyclic carbonates have wide applications, and developing an efficient catalytic system for their synthesis is very important for practical application. Direct synthesis of cyclic carbonates from olefins and CO 2 is simple, inexpensive, environmentally friendly, and a more economic protocol for the utilization of CO 2 . This review article discusses comprehensive developments regarding the protocol catalyzed by single- or multi-component catalytic systems, which are classified into transition metal and transition-metal-free ones. Transition-metal-free systems are mainly achieved through quaternary ammonium salts or ionic liquids containing halides. Besides, noble metal such as Au, Ru, Pd, Pt, non-noble metal for example Ti, Mn, Re, Cr, Mo, Co and lanthanide elements together with quaternary ammonium salts or others construct multi-component catalytic systems containing transition metal. Additionally, halohydrins or epoxides as the intermediates in the corresponding mechanisms are presented to give hints for designing single component multifunctional catalysts or developing new transformation strategies.