2,4- vs 3,4-Disubsituted Pyrrole Synthesis Switched by Copper and Nickel Catalysts
Feng Chen, Tao Shen, Yuxin Cui and Ning Jiao*
*State Key Laboratory of Natural and Biomimetic Drugs, Peking University, School of Pharmaceutical Sciences, Peking University, Xue Yuan Rd. 38, Beijing 100191, China, Email: jiaoningbjmu.edu.cn
F. Chen, T. Shen, Y. Cui, N. Jiao, Org. Lett., 2012, 14, 4926-4929.
DOI: 10.1021/ol302270z (free Supporting Information)
Copper or nickel catalyzed highly selective denitrogenative annulations of vinyl azides with aryl acetaldehydes afford 2,4- and 3,4-diaryl substituted pyrroles depending on the selection of the transition metal catalyst. Compared with the reported acidic or basic conditions for polysubstituted pyrrole synthesis, the reaction conditions are mild, neutral, and very simple without any additives.
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