The Synthesis of Highly Substituted Isoxazoles by Electrophilic Cyclization: An Efficient Synthesis of Valdecoxib
作者:Jesse P. Waldo、Richard C. Larock
DOI:10.1021/jo701942e
日期:2007.12.1
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.
大量官能取代的 2-alkyn-1-one O-甲基肟在温和的反应条件下在 ICl 存在下环化,以中等至极好的收率得到相应的 4-碘异恶唑。所得的 4-碘异恶唑经过各种钯催化反应生成 3,4,5-三取代的异恶唑,包括伐地考昔。