Enantiodivergent C3-Selective Reduction of Arylvinyl-Substituted 3,5-Dicarbonyl Esters Enabled by Engineered Ketoreductases.

Enantioselective Michael addition of N-substituted 3-chlorooxindoles with 1,1-bis(arylsulfonyl)ethylenes: access to 3,3-disubstituted and spirocyclopropane-fused oxindoles.

We report a highly enantioselective organocatalyzed Michael addition of N-substituted 3-chlorooxindoles to 1,1-bis(arylsulfonyl)ethylenes. With a readily available quinine-derived catalyst under mild conditions, this reaction delivers chiral 3,3-disubstituted oxindoles in high yields (up to 93%) and enantioselectivitie...

Diastereo- and Enantioselective Synthesis of 9-Aryl-1-vinyl-tetrahydro-β-carbolines via Brønsted Acid-Catalyzed Pictet-Spengler Reaction.

Reported herein is a stereoselective synthesis of 9-aryl-1-vinyl-tetrahydro-β-carbolines via a Pictet-Spengler reaction. This reaction proceeds via Brønsted acid-catalyzed cyclization of N-indole-tethered allenamides with >20:1 dr under mild conditions, while chiral phosphoric acid catalysis installs the C-N axial chir...

Synthesis of spirobenzoxazine frameworks from biomass-derived chloromethylfurfural via a key intramolecular aza-Piancatelli reaction.

Regioselective Palladium-Catalyzed Direct C3-H Arylation of Triazolopyridazines with Aryl Thianthrenium Salts.

A regioselective palladium-catalyzed C3-H arylation of 1,2,4-triazolo[4,3-b]pyridazines with readily accessible aryl thianthrenium salts has been developed. This method provides direct access to a diverse array of C3-arylated triazolopyridazines in moderate to excellent yields under mild and operationally simple condit...

Cobalt-Catalyzed Enantioselective Intermolecular C–H Carboamination with Racemic Allenes

Enantioselective carboamination of allenes especially in conjunction with 3D-metal catalysis remains a significant challenge. We report chiral cyclopentadienyl cobaltIII-catalyzed regio-, chemo-, and enantioselective intermolecular C–H carboamination of racemic allenyl esters with N-phenoxyisobutyramides. The protoco...

Enantioselective Synthesis of gem -Difluorinated Spirobenzazepinoindoles by Chiral Phosphoric Acid (CPA)-Catalyzed Asymmetric Pictet–Spengler Cyclization

7-membered spirobenzazepinoindole frameworks constitute an important family of heterocyclic skeletons with broad utility in pharmaceutical research. Despite their value, the stereoselective synthetic routes toward chiral gem-difluorinated spirobenzazepinoindoles remain unexplored, and a general, efficient constructio...