Resin-bound 4H-1,3-oxazine-masked beta-diketones for functionalizing cleavage strategy.
Resin-bound 4H-1,3-oxazines are synthesized by the stepwise condensation of an amide resin, an aldehyde, and an alkyne. Upon DDQ activation, oxazines are converted into oxazinium salts. When treated with hydrazines, these resin-bound beta-diketone equivalents yield pyrazoles through a functionalizing release process. This multicomponent capture strategy, tedious to handle in classical synthesis in solution, is well-suited to solid-supported chemistry. It facilitates the handling of sensitive and unstable intermediates, such as N-alpha-methoxyalkylamides and 1,3-oxazinium salts.
Vanier
Cécile
C
Laboratoire de Synthèse Bio-organique, Université Louis Pasteur de Strasbourg, UMR 7514 associée au CNRS, Faculté de Pharmacie, 74 route du Rhin-B.P. 24, 67401 Illkirch CEDEX, France.
Wagner
Alain
A
Mioskowski
Charles
C