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![[(DPEPhos)(bcp)Cu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F59739.jpg&w=3840&q=50)
[(DPEPhos)(bcp)Cu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
Published on: May 21, 2019
Copper-Catalyzed Asymmetric Propargylation of 5-Aminopyrazoles
Vignesh Venkatachalam Pavalakodi1, Ramprasad Begari1, Aman Mourya1
1School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Vithura, Kerala 695551, India.
None:
In this study, we describe a synthetic route to achieve enantioselective synthesis of a broad range of propargylated 5-aminopyrazoles by reacting 5-aminopyrazoles with propargyl acetates in the presence of a chiral Cu(I)-PyBOX complex and Brønsted base. The present catalytic system preferentially enables C-selective propargylation over N-selective propargylation of 5-aminopyrazoles, and the target products were obtained in very high yields (up to 99%) and enantioselectivities (up to 97:3 er). Additionally, a scale-up reaction and postsynthetic modifications of the products have been presented.
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