Copper-Catalyzed Enantioselective [4π + 2σ] Cycloaddition of Bicyclobutanes with Nitrones.
J Am Chem Soc
; 2024 Sep 25.
Article
de En
| MEDLINE
| ID: mdl-39321390
ABSTRACT
The selective construction of bridged bicyclic scaffolds has garnered increasing attention because of their extensive use as saturated bioisosteres of arene in pharmaceutical industry. However, in sharp contrast to their racemic counterparts, assembling chiral bridged bicyclic structures in an enantioselective and regioselective manner remains challenging. Herein, we describe our protocol for constructing chiral 2-oxa-3-azabicyclo[3.1.1]heptanes (BCHeps) by enantioselective [4π + 2σ] cycloadditions of bicyclo[1.1.0]butanes (BCBs) and nitrones taking advantage of a chiral copper(II) complex as a Lewis acid catalyst. This method features mild conditions, good functional group tolerance, high yield (up to 99%), and excellent enantioselectivity (up to 99% ee). Density functional theory (DFT) calculation elucidates the origin of the reaction's enantioselectivity and the mechanism of BCB activation by Cu(II) complex.
Texte intégral:
1
Collection:
01-internacional
Base de données:
MEDLINE
Langue:
En
Journal:
J Am Chem Soc
Année:
2024
Type de document:
Article
Pays d'affiliation:
Chine
Pays de publication:
États-Unis d'Amérique