A trifluoroacetic acid catalyzed highly 6-endo regioselective bromocyclization of styrene-type carboxylic acid has been developed. The resulting 3,4-dihydroisocoumarines are valuable building blocks in organic synthesis.
2.Enantioselective CuH-Catalyzed Reductive Coupling of Aryl Alkenes and Activated Carboxylic Acids.
Bandar JS1, Ascic E1, Buchwald SL1. J Am Chem Soc. 2016 Apr 29. [Epub ahead of print]
A new method for the enantioselective reductive coupling of aryl alkenes with activated carboxylic acid derivatives via copper hydride catalysis is described. Dual catalytic cycles are proposed, with a relatively fast enantioselective hydroacylation cycle followed by a slower diastereoselective ketone reduction cycle. Symmetrical aryl carboxyclic anhydrides provide access to enantioenriched α-substituted ketones or alcohols with excellent stereoselectivity and functional group tolerance.
