High stereoselectivity on low temperature Diels-Alder reactions
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High stereoselectivity on low temperature Diels-Alder reactions
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.
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ژورنال
عنوان ژورنال: Beilstein Journal of Organic Chemistry
سال: 2005
ISSN: 1860-5397
DOI: 10.1186/1860-5397-1-14