Solid phase synthesis of 1,5-disubstituted pyrazole-4-hydroxamic acids and pyrazole-4-carboxamides via direct amidation of β-ketoesters

This manuscript describes a convenient method for the direct amidation of methyl and ethyl β-ketoesters to generate solid-supported β-ketohydroxamates or β-ketoamides and the application of this methodology to the synthesis of 1,5-disubstituted pyrazole-4-hydroxamic acids and pyrazole-4-carboxamides.