Abstract
Iminosugar derivatives containing a pyrrolidine-phosphine moiety were prepared from carbohydrates and used as catalysts in the [3 + 2] cycloaddition reaction between alkyl allenoates and electron-deficient imines. The corresponding 1,2,3,5-tetrasubstituted pyrrolines were obtained in good yields and diastereoselectivities but with moderate enantiocontrol. The stereochemical outcome of the reaction depends on the substituent at the nitrogen atom and hydroxyl groups, the configuration of the stereogenic centers and the distance between the diphenylphosphine group and the pyrrolidine skeleton of the catalyst. The preparation of both enantiomers of the catalyst allowed the corresponding enantiomeric pyrrolines to be obtained with similar yields, diastereo- and enantioselectivities.
Funder
Ministerio de Ciencia e Innovación of Spain
Junta de Andalucía
Subject
Physical and Theoretical Chemistry,Catalysis,General Environmental Science