Base-Free Photoredox/Nickel Dual-Catalytic Cross-Coupling of Ammonium Alkylsilicates
نویسندگان
چکیده
Single-electron transmetalation is recognized as an enabling technology for the mild transfer of alkyl groups to transition metal catalysts in cross-coupling reactions. Hypercoordinate silicates represent a new and improved class of radical precursors because of their low oxidation potentials and the innocuous byproducts generated upon oxidation. Herein, we report the cross-coupling of secondary and primary ammonium alkylsilicates with (hetero)aryl bromides in good to excellent yields. The base-free conditions have exceptional protic group tolerance on both partners, permitting the cross-coupling of unprotected primary and secondary amines.
منابع مشابه
C(sp3)–C(sp2) cross-coupling of alkylsilicates with borylated aryl bromides – an iterative platform to alkylated aryl- and heteroaryl boronates† †Electronic supplementary information (ESI) available: Experimental details and spectral data. See DOI: 10.1039/c6sc03236b Click here for additional data file.
The attractive field of iterative cross-coupling has seen numerous advances, although almost exclusively in the union of sp-hybridized partners. Conspicuously absent from this useful synthetic manifold is the inclusion of sp-hybridized pronucleophiles that can undergo transmetalation under mild conditions. Described here is the use of primary and secondary ammonium alkylsilicates, which undergo...
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