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Mechanistic Studies of Azaphilic versus Carbophilic Activation by Gold(I) in the Gold/Palladium Dual-Catalyzed Rearrangement of Alkenyl Vinyl Aziridines.

ABSTRACT: A vinyl aziridine activation strategy cocatalyzed by palladium(0) and a gold(I) Lewis acid has been developed. This rearrangement installs a C-C and a C-N bond in one synthetic step to form pyrrolizidine and indolizidine products. Two proposed mechanistic roles for the gold cocatalyst were considered: (1) carbophilic gold catalysis or (2) azaphilic gold catalysis. Mechanistic studies support an azaphilic Lewis acid activation of the aziridine over a carbophilic Lewis acid activation of the alkene.

SUBMITTER: Hirner JJ

PROVIDER: S-EPMC3898857 | biostudies-literature | 2012 Oct

REPOSITORIES: biostudies-literature

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Mechanistic Studies of Azaphilic versus Carbophilic Activation by Gold(I) in the Gold/Palladium Dual-Catalyzed Rearrangement of Alkenyl Vinyl Aziridines.

Hirner Joshua J JJ Roth Katrina E KE Shi Yili Y Blum Suzanne A SA

Organometallics 20121001 19

A vinyl aziridine activation strategy cocatalyzed by palladium(0) and a gold(I) Lewis acid has been developed. This rearrangement installs a C-C and a C-N bond in one synthetic step to form pyrrolizidine and indolizidine products. Two proposed mechanistic roles for the gold cocatalyst were considered: (1) carbophilic gold catalysis or (2) azaphilic gold catalysis. Mechanistic studies support an azaphilic Lewis acid activation of the aziridine over a carbophilic Lewis acid activation of the alken ...[more]

PMID: 24465074

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