exo-Selective asymmetric Diels-Alder reaction catalyzed by diamine salts as organocatalysts.
نویسندگان
چکیده
An organocatalyst formed from a binaphthyl-substituted diamine and trifluoromethanesulfonic acid exhibited unprecedented levels of exo selectivity in the Diels-Alder reaction of alpha,beta-unsaturated aldehydes with cyclopentadiene. A novel axially chiral diamine was also designed as an organocatalyst for an asymmetric variant of this reaction, in which the desired cycloadducts were formed with high diastereo- and enantioselectivities. The highest diastereoselectivity observed was greater than 20:1 in favor of the exo cycloadduct in the asymmetric Diels-Alder reaction of crotonaldehyde with cyclopentadiene.
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ورودعنوان ژورنال:
- Organic letters
دوره 8 13 شماره
صفحات -
تاریخ انتشار 2006