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Rhodium(III)-Catalyzed Imidoyl C-H Activation for Annulations to Azolopyrimidines.

ABSTRACT: Azolopyrimidines are efficiently prepared by direct imidoyl C-H bond activation. Annulations of N-azolo imines with sulfoxonium ylides and diazoketones under redox-neutral conditions and alkynes under oxidizing conditions provide products with various arrangements of nitrogen atoms and carbon substituents. We have also probed the mechanism of this first example of Rh(III)-catalyzed direct imidoyl C-H activation by structural characterization of a catalytically competent rhodacycle obtained after C-H activation and by kinetic isotope effects.

SUBMITTER: Halskov KS

PROVIDER: S-EPMC5941131 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature

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Rhodium(III)-Catalyzed Imidoyl C-H Activation for Annulations to Azolopyrimidines.

Halskov Kim Søholm KS Witten Michael R MR Hoang Gia L GL Mercado Brandon Q BQ Ellman Jonathan A JA

Organic letters 20180327 8

Azolopyrimidines are efficiently prepared by direct imidoyl C-H bond activation. Annulations of N-azolo imines with sulfoxonium ylides and diazoketones under redox-neutral conditions and alkynes under oxidizing conditions provide products with various arrangements of nitrogen atoms and carbon substituents. We have also probed the mechanism of this first example of Rh(III)-catalyzed direct imidoyl C-H activation by structural characterization of a catalytically competent rhodacycle obtained after ...[more]

PMID: 29582661

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