Catalytic asymmetric hydrogenation of 3-ethoxycarbonyl quinolin-2-ones and coumarins
A protocol of iridium catalyzed asymmetric hydrogenation of 4-alkyl substituted 3-ethoxycarbonyl quinolin-2-ones and coumarins has been reported, providing a wide range of chiral dihydroquinolin-2-ones and dihydrocoumarins in high yields with excellent enantioselectivities (up to 99% ee) and high turnover numbers (up to 28 000). This efficient protocol was successfully applied for the synthesis of MPR3160 and the key chiral intermediate of R-106578.
Synthesis of 3,4-disubstituted quinolin-2-(1H)-ones via palladium-catalyzed decarboxylative arylation reactions
The Pd-catalyzed decarboxylative cross-coupling reaction of 4-substituted quinolin-2(1H)-one-3-carboxylic acids with (hetero)aryl halides is described. With palladium(II) bromide and triphenylarsine ligand as the catalyst system, a variety of 4-substituted 3-(hetero)aryl quinolin-2(1 H)-ones and related heterocycles, such as 4-substituted 3-arylcoumarins can be prepared in good to excellent yields. Copyright