Asymmetric 1,3-dipolar cycloaddition reaction of nitrones and acrolein with a bis-titanium catalyst as chiral Lewis acid

Taichi Kano; Takuya Hashimoto; Keiji Maruoka

doi:10.1021/ja0523284

Asymmetric 1,3-dipolar cycloaddition reaction of nitrones and acrolein with a bis-titanium catalyst as chiral Lewis acid

J Am Chem Soc. 2005 Aug 31;127(34):11926-7. doi: 10.1021/ja0523284.

Authors

Taichi Kano¹, Takuya Hashimoto, Keiji Maruoka

Affiliation

¹ Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo, Kyoto 606-8502, Japan.

PMID: 16117516
DOI: 10.1021/ja0523284

Abstract

A mu-oxo-type chiral bis-Ti(IV) oxide (S,S)-1 can be successfully utilized in the asymmetric 1,3-dipolar cycloaddition reactions between various nitrones 2 and acrolein to give the corresponding isoxazolidines with high to excellent enantioselectivities. For instance, the reaction between nitrone 2 (R = t-Bu) and acrolein in the presence of 10 mol % of bis-Ti(IV) catalyst (S,S)-1 in dichloromethane at -40 degrees C gave the corresponding endo cycloadduct with 97% ee.