Synthesis of Aminopyrazoles from α- Oxoketene O,N-Acetals Using Montmorillonite K-10/Ultrasound

Abstract

5(3)-Amino-3(5) phenylpyrazoles 3a-f have been conveniently prepared by condensation of α-oxoketene O,N-acetals 2a-g with hydrazine using montmorillonite K-10 as solid support under sonication.

aminopyrazoles - α-oxoketene O,N-Acetals - β-oxothioxo ester - montmorillonite K-10

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