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A novel electron-deficient chiral diphosphine ligand bearing trifluoromethyl groups at the 6- and 6′-positions of the biphenyl backbone, (Sa,R,R)-(CF3)2-C3-TunePhos, has been synthesized from the commercially available chiral 2,4-pentanediol. The above ligand was successfully applied to palladium-catalyzed asymmetric hydrogenation of linear and cyclic α-iminophosphonates with up to 99% ee.

Poly(silyl ethers) (PSEs) are promising degradable materials, and the development of an efficient method to produce them from readily available materials is highly desirable. Herein, we present a dehydrocoupling polymerization of AB-type silyl alcohol monomers catalyzed by homogeneous iridium(I) complexes bearing a bisphosphine ligand. A series of PSEs containing aliphatic or aromatic linkers have been synthesized. The PDI of PSEs could be tuned by varying the ligand of iridium/bisphosphine complexes. Moderate to high yields of polymers with number-average molecular weights (Mn) up to 9.27 × 104 were obtained. The PSEs possess good thermal stability and low glass-transition temperature (Tg = −42 to −83 °C).

An enantioselective iridium-catalyzed direct hydrogenation of heteroaromatics containing two nitrogen atoms, 3-substituted pyrrolo[1,2-a]pyrazines, has been successfully achieved, providing a facile synthesis of optically active 1,2,3,4-tetrahydropyrrolo[1,2-a]pyrazines with up to 96% ee.

An iridium-catalyzed asymmetric hydrogenation/oxidative fragmentation of 6-substituted 5H-benzo[d] benzofuro[3,2-b]azepines has been developed, providing an efficient access to optically active 4-substituted 4,5-dihydro-1H-benzo[d]azepin-1-ones with up to 91% ee. A possible reaction pathway includes the asymmetric hydrogenation to furnish chiral cyclic amines and oxidative fragmentation under an air atmosphere.

An enantioselective hydrogenation of fluorinated hydrazones has been achieved by employing [Pd(R)-DTBM-SegPhos(OCOCF3)2] as the catalyst, providing a general and convenient method toward chiral fluorinated hydrazines. A broad substrate scope including β-aryl-, γ-aryl-, and alkyl-chain-substituted hydrazones worked efficiently in high yields and up to 94% of enantioselectivity. The reductive amination between trifluoromethyl-substituted ketones and benzohydrazides could also proceed smoothly.

An efficient and enantioselective palladium-catalyzed intramolecular asymmetric reductive amination with sulfonylcarbamates as N -sources was reported, providing a facile and general access to the chiral γ -sultam derivatives with up to 97% of enantioselectivity. This tandem process avoids additional deprotection manipulation and arduous isolation of the N -sulfonyl-imine intermediates.

An efficient kinetic resolution of axially chiral 5- or 8-substituted quinoline derivatives was developed through asymmetric transfer hydrogenation of heteroaromatic moiety, simultaneously obtaining two kinds of axially chiral skeletons with up to 209 of selectivity factor. This represents the first successful application of asymmetric transfer hydrogenation of heteroaromatics in kinetic resolution of axially chiral biaryls.