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The influence factors of surfactant-type catalysts system on the asymmetric transfer hydrogenation (ATH) of ketones in water, including the length of aliphatic tail, the concentration of catalysts and the solvent, have been investigated. These factors played significant roles on reaction activity and stereo control. With single-chain surfactant-type catalyst Rh-L4, α, β-unsaturated ketones especially the aliphatic derivatives affords excellent regioselectivities and enantioselectivities.

A chiral double-chain surfactant-type ligand was designed and synthesized. The rhodium catalyst formed from the ligand can self-assemble into chiral vesicular aggregates in water, which was applied to the ATH of a broad range of aromatic ketoesters in neat water and gave up to 99% yield and 99% ee. In addition, this double-chain surfactant-type catalyst could also be applied to the dynamic kinetic resolution (DKR) of bicyclic β-ketoesters in water.

A new flexible C1-symmetric tridentate ligand (S)-N-(2-(tert-butylsulfinyl)benzyl)-1-(pyridin-2-yl)methanamine sulfoxide (L1) was successfully prepared and utilized as a chiral ligand for Ir(I)-catalyzed ATH (asymmetric transfer hydrogenation) reactions. Without any cooperation of other chiral center, encouraging ee and conversion values have been achieved, which provide us a better understanding on these types of ligands and a new strategy to develop new high-efficiency chiral catalysts for asymmetric reaction.

A rhodium complex with an amphiphilic, chiral surfactant-type ligand is applied to the asymmetric transfer hydrogenation of long-chained aliphatic ketoesters.

A series of amphiphilic ligands were designed and synthesized. The rhodium complexes with the ligands were applied to the asymmetric transfer hydrogenation of broad range of long-chained aliphatic ketoesters in neat water. Quantitative conversion and excellent enantioselectivity (up to 99% ee) was observed for α-, β-, γ-, δ- and e-ketoesters as well as for α- and β-acyloxyketone using chiral surfactant-type catalyst 2. The CH/π interaction and the strong hydrophobic interaction of long aliphatic chains between the catalyst and the substrate in the metallomicelle core played a key role in the catalytic transition state. Synergistic effects between the metal-catalyzed site and the hydrophobic microenvironment of the core in the micelle contributed to high stereoselectivity.

As an efficient catalyst for asymmetric transfer hydrogenation reaction (ATH reaction) of α,β-unsaturated ketones, Rh-Cp ∗ –TsDPEN (Cp ∗ = 1,2,3,4,5-pentamethylcyclopenta-1,3-diene, TsDPEN = N -( p -toluenesulfonyl)-1,2-diphenyl- ethylenediamine) shows high chemoselectivity on C O and C C reduction. In our method, both C O and C C bonds in a variety of chromenone derivatives were reduced efficiently in aqueous media, resulting in at least 98% ee and up to 99% yields in a convenient way without further purification. The product was a useful intermediate for deriving chiral chroman-4-amine, which was reported as an effective agent against hypotension and inflammatory pain by inhibiting human bradykinin B1 receptor.

The title rhodium TsDPEN complex efficiently catalyzes the asymmetric transfer hydrogenation of chromenones to produce alcohols (II) with excellent enantioselectivities.