Selective Mono- and Diamination of Ketones in a Combined Copper–Organocatalyst System
Jiabin Shen, Zhihao Wang, Yu‐Ru Zhang, Jun Xu, Xiaogang Liu, Chao Shen, Pengfei Zhang
Abstract
Herein, we report a simple and mild protocol for the chemoselective mono- and diamination of ketone using pyrazole as the amine source in a combined copper–organocatalyst system. Various substrates are compatible, providing the corresponding products in moderate to good yields. This strategy gives an efficient and convenient solution for the synthesis of α-pyrazole and α,α-dipyrazole ketone derivatives. The control experiment demonstrates that in situ generated hydrazone is a key intermediate in the transformation.
Topics & Concepts
ChemistryHydrazoneKetonePyrazoleCombinatorial chemistryCopperAmine gas treatingOrganic chemistryCatalytic C–H Functionalization MethodsSynthesis and Catalytic ReactionsAsymmetric Synthesis and Catalysis