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Zinc-gold cooperative catalysis for the direct alkynylation of benzofurans.

ABSTRACT: The direct alkynylation of benzofurans was achieved for the first time using the hypervalent iodine reagent 1-[(triisopropylsilyl)ethynyl]-1,2-benziodoxol-3(1H)-one (TIPS-EBX) based on the cooperative effect between a gold catalyst and a zinc Lewis acid. High selectivity was observed for C2-alkynylation of benzofurans substituted with alkyl, aryl, halogen and ether groups. The reaction was also successful in the case of the more complex drug 8-methoxypsoralen (8-MOP).

SUBMITTER: Li Y

PROVIDER: S-EPMC3778369 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Zinc-gold cooperative catalysis for the direct alkynylation of benzofurans.

Li Yifan Y Waser Jérôme J

Beilstein journal of organic chemistry 20130829

The direct alkynylation of benzofurans was achieved for the first time using the hypervalent iodine reagent 1-[(triisopropylsilyl)ethynyl]-1,2-benziodoxol-3(1H)-one (TIPS-EBX) based on the cooperative effect between a gold catalyst and a zinc Lewis acid. High selectivity was observed for C2-alkynylation of benzofurans substituted with alkyl, aryl, halogen and ether groups. The reaction was also successful in the case of the more complex drug 8-methoxypsoralen (8-MOP). ...[more]

PMID: 24062840

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