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Pyran annulation: asymmetric synthesis of 2,6-disubstituted-4-methylene tetrahydropyrans.

ABSTRACT: [reaction: see text] A reaction process for the asymmetric construction of a variety of cis or trans disubstituted pyrans is described. This sequences allows for the asymmetric convergent union of two aldehydes with silyl-stannane reagent 1 in a two-step process: catalytic asymmetric allylation of the first aldehyde using 1 with a BITIP catalyst, followed by reaction of the alcohol so obtained with a second aldehyde and TMSOTf.

SUBMITTER: Keck GE

PROVIDER: S-EPMC1480410 | biostudies-literature | 2002 Apr

REPOSITORIES: biostudies-literature

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Pyran annulation: asymmetric synthesis of 2,6-disubstituted-4-methylene tetrahydropyrans.

Keck Gary E GE Covel Jonathan A JA Schiff Tobias T Yu Tao T

Organic letters 20020401 7

[reaction: see text] A reaction process for the asymmetric construction of a variety of cis or trans disubstituted pyrans is described. This sequences allows for the asymmetric convergent union of two aldehydes with silyl-stannane reagent 1 in a two-step process: catalytic asymmetric allylation of the first aldehyde using 1 with a BITIP catalyst, followed by reaction of the alcohol so obtained with a second aldehyde and TMSOTf. ...[more]

PMID: 11922815

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