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On the impact of steric and electronic properties of ligands on gold(I)-catalyzed cycloaddition reactions.

ABSTRACT: It is shown that [4 + 3] and [4 + 2] cycloaddition pathways are accessible in the Au(I) catalysis of allene-dienes. Seven-membered ring gold-stabilized carbenes, originating from the [4 + 3] cycloaddition process, are unstable and can rearrange via a 1,2-H or a 1,2-alkyl shift to yield six- and seven-membered products. Both steric and electronic properties of the AuL(+) catalyst affect the electronic structure of the intermediate gold-stabilized carbene and its subsequent reactivity.

SUBMITTER: Benitez D

PROVIDER: S-EPMC2783583 | biostudies-literature | 2009 Nov

REPOSITORIES: biostudies-literature

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On the impact of steric and electronic properties of ligands on gold(I)-catalyzed cycloaddition reactions.

Benitez Diego D Tkatchouk Ekaterina E Gonzalez Ana Z AZ Goddard William A WA Toste F Dean FD

Organic letters 20091101 21

It is shown that [4 + 3] and [4 + 2] cycloaddition pathways are accessible in the Au(I) catalysis of allene-dienes. Seven-membered ring gold-stabilized carbenes, originating from the [4 + 3] cycloaddition process, are unstable and can rearrange via a 1,2-H or a 1,2-alkyl shift to yield six- and seven-membered products. Both steric and electronic properties of the AuL(+) catalyst affect the electronic structure of the intermediate gold-stabilized carbene and its subsequent reactivity. ...[more]

PMID: 19780543

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