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High stereoselectivity on low temperature Diels-Alder reactions.

ABSTRACT: 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.

SUBMITTER: da Silva Filho LC

PROVIDER: S-EPMC1399462 | biostudies-literature | 2005 Dec

REPOSITORIES: biostudies-literature

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High stereoselectivity on low temperature Diels-Alder reactions.

da Silva Filho Luiz Carlos LC Lacerda Júnior Valdemar V Constantino Mauricio Gomes MG da Silva Gil Valdo José GV Invernize Paulo Roberto PR

Beilstein journal of organic chemistry 20051209 1

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. ...[more]

PMID: 16542029

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