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A Route to the C,D,E Ring System of the Aspidosperma Alkaloids.

ABSTRACT: A short synthetic sequence leading to the formation of the C,D,E-ring subunit of the Aspidosperma alkaloids is reported. This route is based on a ring fragmentation/intramolecular azomethine ylide 1,3-dipolar cycloaddition reaction sequence that gives the desired tricyclic product as a single diastereomer. A ?-amino-?-hydroxy-?-diazo carbonyl compound is shown to fragment in the presence of a Lewis acid to give an iminium product that can be directly reduced to the corresponding amine.

SUBMITTER: Giampa GM

PROVIDER: S-EPMC4994716 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature

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A Route to the C,D,E Ring System of the Aspidosperma Alkaloids.

Giampa Geoffrey M GM Fang Jian J Brewer Matthias M

Organic letters 20160808 16

A short synthetic sequence leading to the formation of the C,D,E-ring subunit of the Aspidosperma alkaloids is reported. This route is based on a ring fragmentation/intramolecular azomethine ylide 1,3-dipolar cycloaddition reaction sequence that gives the desired tricyclic product as a single diastereomer. A γ-amino-β-hydroxy-α-diazo carbonyl compound is shown to fragment in the presence of a Lewis acid to give an iminium product that can be directly reduced to the corresponding amine. ...[more]

PMID: 27500799

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