RING-OPENING OF 4-ISOXAZOLINES: COMPETITIVE FORMATION OF ENAMINO DERIVATIVES AND α,β-ENONES
Ring-opening of 3-substituted 4-isoxazolines, proceeding through the intermediate isoxazolinium salts, follows two competing reaction pathways leading to α,β-enones and enamines respectively.The rearrangement courses can be controlled as a function of substitution pattern and experimental conditions.