A novel chiral bisphosphine-thiourea ligand was developed and applied in the highly enantioselective hydrogenation of β,β-disubstituted nitroalkenes (up to 99% yield and 99% ee). With low catalytic loading (0.25 mol %), 98% ee and 98% conversion were obtained. The thiourea group takes on an important role in this catalytic system.

Catalyzed by a Rh/bisphosphine–thiourea (L1) complex, isoquinolines and quinolines are hydrogenated with high conversions and high enantioselectivities.

Asymmetric hydrogenation of unprotected N-H imines catalyzed by Rh/bisphosphine-thiourea provided chiral amines with up to 97% yield and 95% ee. 1H NMR studies, coupled with control experiments, implied that catalytic chloride-bound intermediates were involved in the mechanism via the dual hydrogen-bonding interaction. Deuteration experiments proved that the hydrogenation proceeded through a pathway consistent with the imine.

Selective and green conversion of chitin to levulinic acid has been realized by catalysis of ionic liquids up to a yield of 67.0%. Two-approach mechanism was proposed in the presence of H-bonding networks mainly contributed by the N-acetyl groups.

A regioselective aromatic π-extension reaction of internal alkynes is reported. The proposed method employs three easily available components, namely aryl halides, 2-haloarylcarboxylic acids, and disubstituted acetylenes. The transformation is driven by a controlled reaction sequence of C-H activation, decarboxylation, and annulation to give poly(hetero)aromatic compounds in a site-selective fashion. Unlike in previously reported palladium-catalyzed three-component annulations, alkyne carbopalladation is the last step of this tandem reaction.

A new catalytic system, generated from the readily available and inexpensive beta-sulfonamide alcohol L*, Ti(O(i)Pr)(4), Et(2)Zn, and tertiary amine base (R(3)N), effectively catalyzes the enantioselective addition of various terminal alkynes including some quite challenging alkynes to aldehydes in good yields and excellent enantioselectivities. Up to 96% yield and >99% enantioselectivity were achieved with the use of N,N-diisoproylethylamine (DIPEA) as an additive in this asymmetric addition.

The asymmetric hydrogenation of β-amino nitroolefins has been successfully achieved by rhodium/bis(phosphine)-thiourea L1 with excellent enantioselectivities and yields (up to 96% ee, 96% yield, >99% conversion, TON up to 1000) under mild conditions. Chiral β-amino nitroalkane products and their derivatives are versatile intermediates in organic synthesis.

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