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Gold-catalyzed Intermolecular [4C + 3C] Cycloaddition Reactions.

ABSTRACT: In the presence of the N-heterocyclic carbene gold catalyst (NHC-AuIPr, 7), propargyl esters 1a-f and 13 undergo a [4C + 3C] cycloaddition reaction with cyclopentadiene and furan under mild conditions. The evidence suggests the formation of the seven-membered ring occurs by a direct cycloaddition process, rather than a stepwise cyclopropanation/Cope rearrangement sequence.

SUBMITTER: Gung BW

PROVIDER: S-EPMC2844647 | biostudies-literature | 2010 Apr

REPOSITORIES: biostudies-literature

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Gold-catalyzed Intermolecular [4C + 3C] Cycloaddition Reactions.

Gung Benjamin W BW Bailey Lauren N LN Wonser Josh J

Tetrahedron letters 20100401 17

In the presence of the N-heterocyclic carbene gold catalyst (NHC-AuIPr, 7), propargyl esters 1a-f and 13 undergo a [4C + 3C] cycloaddition reaction with cyclopentadiene and furan under mild conditions. The evidence suggests the formation of the seven-membered ring occurs by a direct cycloaddition process, rather than a stepwise cyclopropanation/Cope rearrangement sequence. ...[more]

PMID: 20352055

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