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Three-component coupling sequence for the regiospecific synthesis of substituted pyridines.

ABSTRACT: A de novo synthesis of substituted pyridines is described that proceeds through nucleophilic addition of a dithiane anion to an ?,?-unsaturated carbonyl followed by metallacycle-mediated union of the resulting allylic alcohol with preformed trimethylsilane-imines (generated in situ by the low-temperature reaction of lithium hexamethyldisilazide with an aldehyde) and Ag(I)- or Hg(II)-mediated ring closure. The process is useful for the convergent assembly of di- through penta-substituted pyridines with complete regiochemical control.

SUBMITTER: Chen MZ

PROVIDER: S-EPMC3262091 | biostudies-literature | 2012 Jan

REPOSITORIES: biostudies-literature

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Three-component coupling sequence for the regiospecific synthesis of substituted pyridines.

Chen Ming Z MZ Micalizio Glenn C GC

Journal of the American Chemical Society 20111214 2

A de novo synthesis of substituted pyridines is described that proceeds through nucleophilic addition of a dithiane anion to an α,β-unsaturated carbonyl followed by metallacycle-mediated union of the resulting allylic alcohol with preformed trimethylsilane-imines (generated in situ by the low-temperature reaction of lithium hexamethyldisilazide with an aldehyde) and Ag(I)- or Hg(II)-mediated ring closure. The process is useful for the convergent assembly of di- through penta-substituted pyridine ...[more]

PMID: 22103772

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