New Cobalt-Catalyzed Cross-Coupling Reactions of Heterocyclic Chlorides with Aryl and Heteroaryl Magnesium Halides
作者:Paul Knochel、Tobias J. Korn、Gérard Cahiez
DOI:10.1055/s-2003-41460
日期:——
New cobalt-catalyzed cross-coupling between arylmagnesium halides and 2-chloropyridines and related heterocycles occur at low temperature leading to 2-arylated heterocycles in good yields.
Cobalt-Catalyzed Cross-Coupling Reactions of Heterocyclic Chlorides with Arylmagnesium Halides and of Polyfunctionalized Arylcopper Reagents with Aryl Bromides, Chlorides, Fluorides and Tosylates
A range of aromatic organocopper or organomagnesium compounds undergo smooth cross-coupling reactions with aryl bromides, chlorides, fluorides and tosylates, leading to polyfunctionalized aromatics or heterocycles in the presence of cobalt salts (5-7.5 mol%) as catalysts. Very mild reaction conditions are needed and, in the case of cross-coupling with organocopper compounds, Bu4NI (1 equiv) and 4-fluorostyrene (20 mol%) are essential as promoters for successful couplings.