Palladium-Catalyzed Chelation-Assisted Aldehyde C–H Bond Activation of Quinoline-8-carbaldehydes: Synthesis of Amides from Aldehydes with Anilines and Other Amines

Abstract

A palladium-catalyzed chelation-assisted direct aldehyde C−H bond amidation of quinoline-8-carbaldehydes with an amine was developed under mild reaction conditions. A wide range of amides were obtained in good to excellent yields from aldehyde with a variety of aniline derivatives and aliphatic amines. Our methodology was successfully applied to synthesize known DNA intercalating agents and can be easily scaled up to a gram scale.

Rhodium(III)-Catalyzed Coupling of Quinolin-8-carboxaldehydes with CF3–Imidoyl Sulfoxonium Ylides by Chelation-Assisted C(sp2)-H Bond Activation for the Synthesis of Trifluoromethyl-Substituted Enaminones

“…Li and co-workers first developed Rh-catalyzed aldehyde C–H bond amination of 8-quinolinecarbaldehyde using N -chloroamines as activated aminating agents . Subsequently, organic azides, anthranil, and even common amines were applied to the C­(sp 2 )–H amination of aldehydes (Scheme b) . A rhodium­(III)-catalyzed cross-coupling of quinolin-8-carboxaldehydes with sulfoxonium ylides was described by Wang and co-workers, which provides a facile pathway to 1,3-diketones and their enol isomers (Scheme c) .…”