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New and readily available chiral SPIROL-based diphosphinite ligands (SPIRAPO) have been prepared and employed for iridium-catalyzed asymmetric hydrogenations of quinolines, quinoxalines and 2 H -1,4-bezoxazin-2-ones. While the structurally similar ( R , R , R )-SPIRAPO and ( R )-SPINOL-based phosphinites were not the best ligands for these transformations, the ( S , R , R )-diastereomer of SPIRAPO was found to be highly effective ligand for the reduction of 20 different heterocyclic systems with loadings as low as S/C = 10 000. This dearomatizative hydrogenation provided direct access to optically active tetrahydroquinolines in high enantioselectivities (up to 94% ee) and excellent yields (up to 99%), and was used to generate 1.75 g of natural alkaloid (−)-( R )-angustureine. This protocol was subsequently extended to achieve asymmetric hydrogenation of quinoxalines and 2 H -1,4-benzoxazin-2-ones in good to excellent enantioselectivities.