Abstract
Chiral oxacyclic frameworks are prevalent in many natural products and bioactive compounds.
In addition, a number of them are important synthetic intermediates. Thus, the synthesis
of such structures is a significant goal in the field of organic chemistry. However,
the development of catalytic asymmetric cycloetherification for the straightforward
synthesis of these compounds remains a challenge. In this study, we propose the use
of aminothiourea catalysis as an effective way to accomplish such a challenge. The
asymmetric synthesis of chiral oxygen heterocycles, including tetrahydrofurans, tetrahydropyrans,
and 1,3-dioxolanes, is demonstrated herein using intramolecular oxy-Michael addition
mediated by bifunctional aminothiourea catalysts.
Key words
oxycyclization - cycloetherification - hydrogen bonding - bifunctional aminothiourea
catalyst - oxy-Michael addition