Visible-Light-Induced Organobismuth(III)-Initiated Halogen-Atom Transfer for the Alkylation of Heterocycles with
Gaofeng Feng1, Chao Zhang1, Tao Cai1
1Shangyu College and Zhejiang Key Laboratory of Alternative Technologies for Fine Chemicals Process, Shaoxing University, Shaoxing 312000, P. R. China.
Abstract:
Employing a trace amount of BiPh3 as a new and sole XAT reagent, a visible-light-induced XAT-enabled protocol for the Minisci alkylation of heterocycles with unactivated iodoalkanes was disclosed. Broad substrate scope and practical applicability were demonstrated by 38 examples with up to 98% yield. Preliminary mechanistic investigations, including DFT calculations, demonstrated a radical pathway. This method features simple operation, no precaution against moisture and oxygen, and EtOH as a green solvent.
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