Synthesis of Highly Functionalized Indolizines via NIS-Promoted Spiroannulation/Ring-Opening Aromatization of
Luan-Ting Wu1, Honglin Diao2, Yi Wu2
1School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu 241000, P. R. China.
Abstract:
A novel NIS-promoted domino reaction of alkylidene oxindoles with 2-(pyridin-2-yl)acetate derivatives has been established, enabling the efficient and straightforward synthesis of a vast variety of highly functionalized indolizines via sequential spiroannulation and ring-opening aromatization processes. The protocol features mild reaction conditions, broad substrate scope, high efficiency, scalability, and applicability for the preparation of CF3-containing indolizines. Furthermore, the functional groups in the indolizine framework provide the feasibility for follow-up derivatization. Based on mechanistic studies, a plausible radical mechanism is proposed to elucidate the formation of indolizines.
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