Ag2O-promoted ring-opening reactions of cyclopropenones with oximes.

Ag2O-promoted ring-opening reactions of cyclopropenones with oximes is disclosed in this work, providing a direct route to 1,3-oxazinones. This method highlights a new reactivity of cyclopropenones which undergo 1,4-addition with oximes followed by ß-carbon elimination to in situ generate a α-carbonyl ketene intermediate.

Three-Component Reactions of Alkynone o-Methyloximes, Element Selenium, and Boronic Acids Leading to 4-Organoselenylisoxazoles.

We report an Ag-catalyzed one-pot three-component reaction of alkynone o-methyloxime, element selenium, and boronic acid, providing a facile route to selenated isoxazole product. This protocol features high efficiency, wide substrate scope, and the use of selenium powder as the selenium source.