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

Tadashi Ema; Maki Yokoyama; Sagiri Watanabe; Sota Sasaki; Hiromi Ota; Kazuto Takaishi

doi:10.1021/acs.orglett.7b01838

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

Org Lett. 2017 Aug 4;19(15):4070-4073. doi: 10.1021/acs.orglett.7b01838. Epub 2017 Jul 27.

Authors

Tadashi Ema¹, Maki Yokoyama¹, Sagiri Watanabe¹, Sota Sasaki¹, Hiromi Ota¹, Kazuto Takaishi¹

Affiliation

¹ Division of Applied Chemistry, Graduate School of Natural Science and Technology, and ‡Advanced Science Research Center, Okayama University , Tsushima, Okayama 700-8530, Japan.

PMID: 28749142
DOI: 10.1021/acs.orglett.7b01838

Abstract

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

Publication types

Research Support, Non-U.S. Gov't