Transformation of 5-acylated N-fluoroalkyl-1,2,3-triazoles to trifluoromethylated ring-fused isoquinolines, 1,3-oxazines, and 1,3-oxazin-6-ones via ketenimines

A one-pot multistep methodology leading to trifluoromethylated cyclopenta[c]isoquinolines, indeno[1,2-c]isoquinolines, 6,6-difluoro-1,3-oxazines, or 1,3-oxazin-6-ones, based on the reaction of 5-acylated N-pentafluoroethyl-substituted 1,2,3-triazoles is presented. A thermal ring opening of the starting triazoles, followed by a 1,2-acyl shift formed reactive ketenimines which cyclized after a rearrangement in a substrate-specific manner to provide new trifluoromethylated heterocyclic products.

Palladium-Catalyzed Tandem C(sp3)-H Insertion Cyclization of 2-(2-Vinylarene)acetonitriles with Isocyanides to Access Naphthalen-2-amines

A Pd-catalyzed cyclization reaction of 2-(2-vinylarene)acetonitriles and isocyanides has been documented. Various naphthalen-2-amines were obtained in moderate to good yields under mild conditions. The in vitro cytotoxicity of all products was evaluated by MTT assay against seven human cancer cell lines. The results indicated that compounds 3ea, 3ma, and 3ob exhibited effective anticancer activities against the tested cancer cells.

Palladium-Catalyzed Preparation of N-Substituted Benz[c,d]indol-2-imines and N-Substituted Amino-1-naphthylamides

Here, we report a novel and facile protocol for the synthesis of benz[c,d]indol-2-imines via palladium-catalyzed C-C and C-N coupling of 8-halo-1-naphthylamines with isocyanides in a single step. The reaction features broad substrate scopes and mild conditions, providing an efficient alternative for the construction of antiproliferative agents and BET bromodomain inhibitors. If 0.1 mL of H₂O was added to this reaction, the N-substituted amino-1-naphthylamides could be obtained easily.

Rh(III)-Catalysed Cascade C-H Imidization/Cyclization of N-Methoxybenzamides with Isoxazolones for the Assembly of Dihydroquinazolin-4(1H)-one Derivatives

By virtue of isoxazolones as viable imidizating reagents, an efficient Rh(III)-catalysed redox-neutral C-H imidization/cyclization cascade has been developed for the specific assembly of dihydroquinazolin-4(1H)-ones with the equipment of a quaternary...

Divergent Reaction of Isocyanides with o-Bromobenzaldehydes: Synthesis of Ketenimines and Lactams with Isoindolinone Cores

A divergent reaction of isocyanides with o-bromobenzaldehydes for the synthesis of isoindolinone-derived ketenimines and lactams was disclosed. The reaction features readily available reactants, relatively mild conditions, and high yields of products. Ketenimines could be applied in further transformations for access to other functional molecules. A mechanism study showed that the palladium-migration/imine-insertion process was the key step in this reaction.