Enantioselective synthesis of axially chiral multifunctionalized biaryls via asymmetric Suzuki-Miyaura coupling.

Substituted 2-formylarylboronic acids were successfully employed as substrates for asymmetric Suzuki-Miyaura coupling. By virtue of the coupling with dialkoxyphosphinyl substituted naphthyl bromides and 2-nitronaphthalen-1-yl triflouromethanesulfonate, a series of novel multifunctionalized axially chiral biaryls were prepared in 53-97% yields with up to 97% ee using palladium-Cy-MOP as the catalyst. The methodology provides a highly efficient and practical strategy for the synthesis of novel multifunctionalized axially chiral biaryls.

Highly efficient synthesis of heterocyclic and alicyclic β2-amino acid derivatives by catalytic asymmetric hydrogenation.

A valuable class of new heterocyclic and alicyclic prochiral α-aminomethylacrylates has been conveniently synthesized through a three-step transformation involving a Baylis-Hillman reaction, O-acetylation, and a subsequent allylic amination. The corresponding novel β(2)-amino acid derivatives were prepared with excellent enantioselectivities and high yields by catalytic asymmetric hydrogenation using the catalyst rhodium(Et-Duphos) (Et-Duphos = 2',5',2'',5''-tetraethyl-1,2-bis(phospholanyl)benzene)) under mild reaction conditions (up to 99 % ee and S/C = 1000). The influence of the substrate on the enantioselectivity and reactivity is investigated, and the most suitable substrate configuration for the highly efficient enantioselective hydrogenation of β-substituted α-aminomethylacrylates under the Rh-Duphos system is reported.