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The first enantioselective Nazarov cyclization of substrates with only one coordinating site and with proton-transfer as an enantioselective-determining step was realized by means of cooperative catalysis with a Lewis acid and a chiral Brønsted acid., Enantioselective control of the chirality of a tertiary α-carbon in the products of a Nazarov cyclization of enones is challenging because the reaction involves an enantioselective proton transfer process. We herein report the use of cooperative catalysis using Lewis acids and chiral Brønsted acids to control the stereochemistry of the tertiary α-carbon in the products of this reaction. Specifically, with ZnCl2 and a chiral spiro phosphoric acid as catalysts, we realized the first enantioselective construction of cyclopenta[b]indoles with chiral tertiary α-carbons via Nazarov cyclization of indole enone substrates with only one coordinating site. Mechanistic studies revealed that the chiral spiro phosphoric acid acts as a multifunctional catalyst: it co-catalyzes the cyclization of the dienone and enantioselectively catalyzes a proton transfer reaction of the enol intermediate. This new strategy of enantioselective control by means of cooperative catalysis may show utility for other challenging asymmetric cyclization reactions.

A bioinspired enantioselective synthesis of crinine-type alkaloids was developed by iridium-catalyzed asymmetric hydrogenation of enones, providing 24 crinine-type alkaloids and 8 analogues with high yield and high enantioselectivity., A bioinspired enantioselective synthesis of crinine-type alkaloids has been developed by iridium-catalyzed asymmetric hydrogenation of racemic cycloenones. The method features a biomimetic stereodivergent resolution of the substrates bearing a remote arylated quaternary stereocenter. Using this protocol, 24 crinine-type alkaloids and 8 analogues were synthesized in a concise and rapid way with high yield and high enantioselectivity.

The first regioselective catalytic asymmetric [3 + 2] cycloaddition of benzofuranone-derived olefins with allenoates and substituted allenoates has been developed in the presence of (R)-SITCP., The first regioselective catalytic asymmetric [3 + 2] cycloaddition of benzofuranone-derived olefins with allenoates and substituted allenoates has been developed in the presence of (R)-SITCP, affording different functionalized 3-spirocyclopentene benzofuran-2-ones in good yields with high enantioselectivities under mild conditions. The substrate scope has also been examined. The regioselective outcomes for this phosphine-catalyzed [3 + 2] cycloaddition reaction can be rationalized using DFT calculations.

A new iridium catalyst containing an imine–diphosphine ligand was developed for the hydrogenation of CO2 to formate., A new iridium catalyst containing an imine–diphosphine ligand has been developed, which showed high efficiency for the hydrogenation of CO2 to formate (yield up to 99%, TON up to 450 000). A possible catalytic mechanism is proposed, in which the imine group of the catalyst plays a key role in the cleavage of H2 and the activation of CO2.

An asymmetric hydrovinylation of silyl-protected allylic alcohols catalyzed by nickel complexes of chiral spiro phosphoramidite ligands was developed. A series homoallylic alchols with a chiral quaternary center were produced in high yields (up to 97%) and high enantioselectivities (up to 95% ee). The reaction provided an efficient method for preparing bifunctional compounds with a chiral quaternary carbon center.

A series of chiral enantiomerically pure mercaptoaryl-oxazolines has been synthesized. Copper(I) thiolate complexes derived from these ligands proved to be efficient catalysts for the 1,4-addition of Grignard reagents to cyclic enones. Enantioselectivities increased in the sequence cyclopentenone (16–37% ee)

Alkylated terrylenes can be synthesized by a twofold cyclization of an appropriately substituted trinaphthyl[1, 11]. In this paper, we consider a special case. The alkyl substitution in the starting material 1 strongly affects the interplanar angle between the naphthalene moieties. After cyclization, the substituents are positioned in the sterically crowded bay region of the title structure 2. The influence of the steric strain on the reactivity of 1 and on the stability of the resulting hydrocarbon 2 is investigated. Special emphasis is placed on the crystal structures of 1 and 2.