Highly diastereoselective Diels-Alder reaction using a chiral auxiliary derived from levoglucosenone
Ariel M Sarotti1, Rolando A Spanevello, Alejandra G Suárez
1Instituto de Química Organica de Síntesis, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario - CONICET Suipacha 531, S2002LRK Rosario, Argentina.
Abstract:
[reaction: see text] A new chiral auxiliary derived from levoglucosenone is reported. The compound is obtained by a cycloaddition reaction with 9-methoxy methylanthracene followed by a diastereoselective reduction of the C-2 keto function. The auxiliary has been used as a chiral template in an asymmetric Diels-Alder reaction of the corresponding acrylic ester derivative with cyclopentadiene. The results showed excellent diastereomeric excess even at room temperature when the reaction was promoted by Et(2)AlCl as the Lewis acid.
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