Bifunctional Metalloporphyrins-Catalyzed Coupling Reaction of Epoxides and CO2 to Cyclic Carbonates

Abstract

Abstract New catalysts of water soluble bifunctional metalloporphyrins M(TTMAPP)I 4 (X) (M = Co, Fe, Mn, and Cr; X = OAc, CF 3 COO, CCl 3 COO, OTs, Cl, Br, and I) were synthesized and used to catalyze the synthesis of cyclic carbonate through the coupling reaction of terminal epoxides and CO 2 . The effects of reaction temperature, various metals as the Lewis acidic center, counterions, and recycling of the catalysts were studied. 5,10,15,20- Tetra -( p - N , N , N -trimethylphenyl ammonium iodide)porphyrinium cobalt(III) acetate [Co(III)(TTMAPP) I 4 (OAc)] was efficient in the coupling reaction of various terminal epoxides and CO 2 at 353 K under 667 kPa of CO 2 pressure without solvent and molar ratio of epoxide:catalyst = 1000. It gave a propylene carbonate yield of 95.4% within 5 h. At 298 K in the presence of 1 ml methanol with the molar ratio of epoxide:catalyst = 2000, it gave a propylene carbonate yield of 19.4% within 24 h. The catalyst could be recovered with diethyl ether and reused five times without significant loss of catalytic activity.