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

JP Waldo, RC Larock

Index: Waldo, Jesse P.; Larock, Richard C. Journal of Organic Chemistry, 2007 , vol. 72, # 25 p. 9643 - 9647

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Citation Number: 237

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.