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Please login to access the full content or check if you have access via Method 3: Reactions Involving Deprotonation of Isoxazolium Salts

DOI: 10.1055/sos-SD-011-00361

Wakefield, B.J.Science of Synthesis, (200211280.

Isoxazolium salts may undergo α-deprotonation of 2- (rarely), 3-, or 5-alkyl substituents (as well as competitive nucleophilic addition and/or ring-opening reactions). In the case of 3,5-dimethylisoxazolium salts, the proportional deprotonation of the 3- and 5-methyl groups depends on the base and on the nature of the 4-substituent.[‌297‌,‌298‌] For isoxazolium salts, tertiary amines are usually sufficiently strong bases. For example, 5-aryl-2,3-dimethylisoxazolium salts 133 condense with aromatic aldehydes in the presence of piperidine (Scheme 78).[‌223‌]

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