Chiral diene-promoted room temperature conjugate arylation: highly enantioselective synthesis of substituted chiral phenylalanine derivatives and α,α-di(arylmethyl)acetates

Rhodium-Catalyzed Asymmetric 1,4-Addition of α/β-(N-Indolyl) Acrylates

A rhodium-catalyzed asymmetric 1,4-addition of α/β-(N-indolyl) acrylates to access highly enantioenriched chiral N-alkylindoles promoted by chiral diene or sulfur-olefin ligands under mild reaction conditions has been developed, which provides an efficient and practical approach for constructing carbon stereocenters adjacent to the indole nitrogen. The reaction can be applied to various N-indolyl-substituted α,β-unstaturated esters and arylboron reagents, providing access to a wide range of α- and β-(N-indolyl) propionate derivatives in high yields with excellent enantioselectivities (≤99% ee).

Synthesis of Polysubstituted 1,2-Dihydro-3H-pyrrolo[1,2-a]indol-3-ones through Domino Palladium-Catalyzed Reactions of Indol-2-ylmethyl Acetates with 1,3-Dicarbonyl Derivatives

A straightforward assembly of polysubstituted 1,2-dihydro-3H-pyrrolo[1,2-a]indol-3-ones through a domino palladium-catalyzed reaction of indol-2-ylmethyl acetates with 1,3-dicarbonyl derivatives is described. The key role of the features of the 1,3-dicarbonyls on the reaction outcome has been explored. The employment of 2-methylcyclohexan-1,3-dione as the dicarbonyl source could allow further challenging indole nucleus functionalizations.

Water as a Direct Proton Source for Asymmetric Hydroarylation Catalyzed by a Rh(I)-Diene: Access to Nonproteinogenic β2/γ2/δ2-Amino Acid Derivatives

A highly enantioselective rhodium-catalyzed intermolecular hydroarylation of α-aminoalkyl acrylates using water as a direct proton source has been realized by employing a chiral bicyclo[3.3.0] diene ligand, allowing efficient access to a broad range of α-aryl-methyl-substituted β²-, γ²-, and δ²-amino esters with excellent enantioselectivities (up to 98% ee) under exceptionally mild conditions. By utilizing this method, a series of structurally interesting benzo-fused heterocyclic molecules and the corresponding β²-, γ²-, and δ²-amino acids are facilely constructed.