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C2-symmetric bisamidines: chiral Bronsted bases catalysing the Diels-Alder reaction of anthrones.

ABSTRACT: C(2)-symmetric bisamidines 8 have been tested as chiral Brønsted bases in the Diels-Alder reaction of anthrones and N-substituted maleimides. High yields of cycloadducts and significant asymmetric inductions up to 76% ee are accessible. The proposed mechanism involves proton transfer between anthrone and bisamidine, association of the resulting ions and finally a cycloaddition step stereoselectively controlled by the chiral ion pair.

SUBMITTER: Akalay D

PROVIDER: S-EPMC2533436 | biostudies-literature | 2008

REPOSITORIES: biostudies-literature

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C2-symmetric bisamidines: chiral Brønsted bases catalysing the Diels-Alder reaction of anthrones.

Akalay Deniz D Dürner Gerd G Bats Jan W JW Göbel Michael W MW

Beilstein journal of organic chemistry 20080807

C(2)-symmetric bisamidines 8 have been tested as chiral Brønsted bases in the Diels-Alder reaction of anthrones and N-substituted maleimides. High yields of cycloadducts and significant asymmetric inductions up to 76% ee are accessible. The proposed mechanism involves proton transfer between anthrone and bisamidine, association of the resulting ions and finally a cycloaddition step stereoselectively controlled by the chiral ion pair. ...[more]

PMID: 18941500

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