The generation of nucleophiles from the combination of aryl boronic acids and catalytic amounts of copper salt allows a reactivity distinct from other organometallic species, such as organolithiums or Grignard reagents. Here we examine how the electronic and steric properties of the boronic acid affect the formation of active nucleophiles and their subsequent reactivity with iminium‐type compounds
Enantioselective, Nickel-Catalyzed Suzuki Cross-Coupling of Quinolinium Ions
作者:Jason D. Shields、Derek T. Ahneman、Thomas J. A. Graham、Abigail G. Doyle
DOI:10.1021/ol4031364
日期:2014.1.3
Quinolinium ions are engaged in an asymmetric, Ni-catalyzed Suzuki cross-coupling to yield 2-aryl- and 2-heteroaryl-1,2-dihydroquinolines. Key to the development of this method is the use of a Ni(II) precatalyst that activates without the need for strong reductants or high temperatures. The Ni-iminium activation mode is demonstrated as an exceptionally mild pathway to generate enantioenriched products from racemic starting materials.