Synthesis of 3-Iminoindol-2-amines and Cyclic Enaminones via Palladium-Catalyzed Isocyanide Insertion-Cyclization
Yuan-Yuan Pan1, Ya-Nan Wu1, Zhen-Zhen Chen1
1†School of Chemistry and Chemical Engineering, Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional Materials, Jiangsu Normal University, Xuzhou 221116, P. R. China.
Abstract:
A palladium-catalyzed isocyanide insertion-cyclization using low-cost and readily accessible 2-haloanilines, 2-iodophenylethanones, and isocyanides for efficient synthesis of 3-iminoindol-2-amine and cyclic enaminone derivatives has been developed. The method features low-cost and readily accessible starting materials, reliable scalability, and bond-forming efficiency as well as simple one-pot operation, which makes this strategy highly attractive. A reasonable mechanism for forming 3-iminoindol-2-amine involved double isocyanide insertion/cyclization process is proposed.
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