High stereoselectivity on low temperature Diels-Alder reactions
نویسندگان
چکیده
We have found that some of the usually poor dienophiles (2-cycloenones) can undergo Diels-Alder reaction at -78 degrees C with unusually high stereoselectivity in the presence of niobium pentachloride as a Lewis acid catalyst. A remarkable difference in reaction rates for unsubstituted and alpha- or beta-methyl substituted 2-cycloenones was also observed.
منابع مشابه
Diels-alder reaction of 2(1H)-pyridones acting as dienes.
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ورودعنوان ژورنال:
- Beilstein Journal of Organic Chemistry
دوره 1 شماره
صفحات -
تاریخ انتشار 2005