Asymmetric Aminations and Kinetic Resolution of Acyclic α-Branched Ynones

An efficient method for asymmetric synthesis of acyclic alpha-tertiary amine derivatives has been achieved through enantioselective aminations of alpha-branched ynones with azodicarboxylates enabled by chiral phosphoric acid catalysis. Moreover, kinetic resolution of racemic starting material was realized under these conditions, which gave access to valuable enantioenriched alpha-substituted ketones. A wide array of alpha-aryl and alkyl-substitutions, and the substituted alkynyl groups were well compatible with this method, producing both the amination products and the recovered ketones with good to high enantioselectivities. [GRAPHICS] .

Automated summary

An efficient method for asymmetric synthesis of acyclic alpha-tertiary amine derivatives has been achieved through enantioselective aminations of alpha-branched ynones with azodicarboxylates enabled by chiral phosphoric acid catalysis. The method is compatible with a wide array of alpha-aryl and alkyl-substitutions, and the substituted alkynyl groups, producing both the amination products and the recovered ketones with good to high enantioselectivities.