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On the validity of Au-vinylidenes in the gold-catalyzed 1,2-migratory cycloisomerization of skipped propargylpyridines.

ABSTRACT: A mechanism of the Au-catalyzed cycloisomerization of propargylpyridines has been investigated. Both DFT computational and experimental results strongly support generation of a Au-carbene via a cyclization/proton transfer sequence over the previously proposed path involving a Au-vinylidene intermediate. For the ?-Si-substituted Au-carbene (G = SiR(3)), a 1,2-Si migration was shown to be kinetically favored over a 1,2-H shift. This study highlights the importance of alternative pathways that could explain reactivities commonly attributed to an alkyne-vinylidene isomerization in Au catalysis.

SUBMITTER: Xia Y

PROVIDER: S-EPMC3131136 | biostudies-literature | 2010 Dec

REPOSITORIES: biostudies-literature

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On the validity of Au-vinylidenes in the gold-catalyzed 1,2-migratory cycloisomerization of skipped propargylpyridines.

Xia Yuanzhi Y Dudnik Alexander S AS Li Yahong Y Gevorgyan Vladimir V

Organic letters 20101111 23

A mechanism of the Au-catalyzed cycloisomerization of propargylpyridines has been investigated. Both DFT computational and experimental results strongly support generation of a Au-carbene via a cyclization/proton transfer sequence over the previously proposed path involving a Au-vinylidene intermediate. For the β-Si-substituted Au-carbene (G = SiR(3)), a 1,2-Si migration was shown to be kinetically favored over a 1,2-H shift. This study highlights the importance of alternative pathways that coul ...[more]

PMID: 21069991

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