Chiral Macrocyclic Organocatalysts for Kinetic Resolution of Disubstituted Epoxides with Carbon Dioxide

• DOI: 10.1021/acs.orglett.7b01838
• Publication Date: 2017-07-27T16:46:16Z
• Authors: Tadashi Ema; Maki Yokoyama; Sagiri Watanabe; Sota Sasaki; Hiromi Ota; Kazuto Takaishi
• Keywords: Kinetic resolution

Among chiral macrocycles 1 synthesized, 1m with the 3,5-bis(trifluoromethyl)phenylethynyl group was best organocatalyst for enantioselective synthesis of cyclic carbonates from disubstituted or monosubstituted epoxides and CO2. The X-ray crystal structure revealed a well-defined cavity multiple hydrogen-bonding sites that is suitable activation epoxides. A catalytic cycle proposed supported by DFT calculations.