Tetrahedron letters

Selective ring N-protection of aminopyrazoles

W Seelen, M Schäfer, A Ernst

Index: Seelen, Werner; Schaefer, Martina; Ernst, Alexander Tetrahedron Letters, 2003 , vol. 44, # 24 p. 4491 - 4493

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Citation Number: 11

Abstract

Two simple procedures for the selective protection of the ring N of aminopyrazoles as tert- butoxycarbamate (Boc) in high yields are reported; several other protecting groups (Cbz, Bn, SEM) can be introduced using the one-pot procedure (method B). The N-Boc protected aminopyrazoles are acylated at the exocyclic NH2 group and subsequently deprotected to give the corresponding 3-acylaminopyrazoles in high yields. This procedure is applicable ...