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Remote C-H insertion of vinyl cations leading to cyclopentenones.

ABSTRACT: We report a Lewis acid catalyzed reaction sequence involving a 1,2-shift and subsequent C-H insertion that gives monocyclic and fused bicyclic cyclopentenone products. This reaction sequence, which is initiated by treating β-hydroxy-α-diazo ketones with a Lewis acid, proceeds through vinyl cation intermediates that insert at non-activated gamma C-H bonds. This reaction represents an alternative strategy to exploit the diazo functional group in an intramolecular C-H insertion, and can provide products not accessible by transition metal catalyzed C-H insertions. This remote C-H activation process provides good yields of bicyclic cyclopentenone products that contain 7- and 8-membered rings, and monocyclic prostaglandin analogs.

SUBMITTER: Cleary SE

PROVIDER: S-EPMC5643953 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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Remote C-H insertion of vinyl cations leading to cyclopentenones.

Cleary Sarah E SE Hensinger Magenta J MJ Brewer Matthias M

Chemical science 20170803 10

We report a Lewis acid catalyzed reaction sequence involving a 1,2-shift and subsequent C-H insertion that gives monocyclic and fused bicyclic cyclopentenone products. This reaction sequence, which is initiated by treating β-hydroxy-α-diazo ketones with a Lewis acid, proceeds through vinyl cation intermediates that insert at non-activated gamma C-H bonds. This reaction represents an alternative strategy to exploit the diazo functional group in an intramolecular C-H insertion, and can provide pro ...[more]

PMID: 29147505

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