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The synthesis of highly substituted isoxazoles by electrophilic cyclization: an efficient synthesis of valdecoxib.

ABSTRACT: A large number of functionally substituted 2-alkyn-1-one O-methyl oximes have been cyclized under mild reaction conditions in the presence of ICl to give the corresponding 4-iodoisoxazoles in moderate to excellent yields. The resulting 4-iodoisoxazoles undergo various palladium-catalyzed reactions to yield 3,4,5-trisubstituted isoxazoles, including valdecoxib.

SUBMITTER: Waldo JP

PROVIDER: S-EPMC2529460 | biostudies-literature | 2007 Dec

REPOSITORIES: biostudies-literature

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The synthesis of highly substituted isoxazoles by electrophilic cyclization: an efficient synthesis of valdecoxib.

Waldo Jesse P JP Larock Richard C RC

The Journal of organic chemistry 20071103 25

A large number of functionally substituted 2-alkyn-1-one O-methyl oximes have been cyclized under mild reaction conditions in the presence of ICl to give the corresponding 4-iodoisoxazoles in moderate to excellent yields. The resulting 4-iodoisoxazoles undergo various palladium-catalyzed reactions to yield 3,4,5-trisubstituted isoxazoles, including valdecoxib. ...[more]

PMID: 17979295

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