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Isomerization-linear-hydroformylation is demanding, however, not an addressed issue, for production of value-added linear aldehydes by converting cheap and abundant internal alkenes available from bio- & petrochemical industry. In this paper, a dual metal catalysis system combining a Ru-isomerization catalyst and a Rh-linear-hydroformylation catalyst satisfying the “4S” criterions was reported for isomerization-linear-hydroformylation of C4 raffinate (mixed butenes) and internal olefins. The optimized dual metal catalyst system hydroformylated Raffinate II feed to valuable valeraldehyde in 98% linear selectivity (n:i = 49), 80% conversion and high activity of 1069 h⁻¹ TOF whereas 96% linear selectivity (n:i = 24), 71% conversion and 948 h⁻¹ TOF were observed using only the Rh-hydroformylation catalyst. Notably, valeraldehyde are produced in million tons scale annually for making non-toxic plasticizer DPHP. Various 2-olefins were also converted to linear aldehydes in > 98% linear selectivity (n:i > 49), 78%–82% conversion and high activity of 802–851 h⁻¹ TOF.

We herein report an efficient method to synthesize cyclic hydroxy ketones with a chiral quaternary center., We herein report an efficient method to synthesize cyclic hydroxy ketones with a chiral quaternary center. Catalyzed by an Ir/f-ampha complex, cyclic α,α-disubstituted 1,3-diketones were hydrogenated, giving mono-reduced products with both high enantioselectivities and diastereoselectivities. In addition, C 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 C and C 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 C bonds could survive in this catalytic system. This method was applied in the preparation of (+)-estrone. No diols were observed in this chemical transformation. The enantiomeric and diastereomeric induction were achieved as a result of steric hindrance.

Rh-Catalyzed asymmetric hydrogenation of substituted benzo[b]thiophene 1,1-dioxides was successfully developed. Both aromatic and alkyl substituted benzo[b]thiophene 1,1-dioxide substrates worked well with high yields and excellent enantioselectivities., Rh-catalyzed asymmetric hydrogenation of prochiral substituted benzo[b]thiophene 1,1-dioxides was successfully developed, affording various chiral 2,3-dihydrobenzo[b]thiophene 1,1-dioxides with high yields and excellent enantioselectivities (up to 99% yield and >99% ee). In particular, for challenging substrates, such as aryl substituted substrates with sterically hindered groups and alkyl substituted substrates, the reaction proceeded smoothly in our catalytic system with excellent results. The gram-scale asymmetric hydrogenation proceeded well with 99% yield and 99% ee in the presence of 0.02 mol% (S/C = 5000) catalyst loading. The possible hydrogen-bonding interaction between the substrate and the ligand may play an important role in achieving high reactivity and excellent enantioselectivity.

An enantioselective synthesis of dibenz[c,e]azepines containing both central and axial chiralities through a one pot N-Boc deprotection/intramolecular asymmetric reductive amination sequence has been achieved with generally excellent enantiocontrol (up to 97% ee)., An Ir-catalyzed intramolecular asymmetric reductive amination (ARA) of bridged biaryl derivatives has been described. Using this unprecedented approach, synthetically useful dibenz[c,e]azepines containing both central and axial chiralities are obtained with excellent enantiocontrol (up to 97% ee). This methodology represents a rare example of enantioselective chemocatalytic synthesis of chiral dibenz[c,e]azepines featuring a broad substrate scope, and their synthetic utilities are exhibited by derivatizing the products into a chiral amino acid derivative and chiral phosphoramidite ligands, which display excellent enantiocontrol in Rh-catalyzed asymmetric hydrogenation of α-dehydroamino acid derivatives. Remarkably, our method is also applicable to enantioselectively synthesize an allocolchicine analogue.

We herein report an efficient method to synthesize cyclic hydroxy ketones with a chiral quaternary center., We herein report an efficient method to synthesize cyclic hydroxy ketones with a chiral quaternary center. Catalyzed by an Ir/f-ampha complex, cyclic α,α-disubstituted 1,3-diketones were hydrogenated, giving mono-reduced products with both high enantioselectivities and diastereoselectivities. In addition, CC and CC bonds could survive in this catalytic system. This method was applied in the preparation of (+)-estrone. No diols were observed in this chemical transformation. The enantiomeric and diastereomeric induction were achieved as a result of steric hindrance.

The Ni-catalyzed asymmetric hydrogenation of challenging β-acylamino nitroolefins was achieved under mild conditions, affording β-acylamino nitroalkanes in excellent yields and with high enantioselectivities., An efficient approach for synthesizing chiral β-amino nitroalkanes has been developed via the Ni-catalyzed asymmetric hydrogenation of challenging β-amino nitroolefins under mild conditions, affording the desired products in excellent yields and with high enantioselectivities. This protocol had good compatibility with the wide substrate scope and a range of functional groups. The synthesis of chiral β-amino nitroalkanes on a gram scale has also been achieved. In addition, the reaction mechanism was elucidated using a combined experimental and computational study, and it involved acetate-assisted heterolytic H2 cleavage followed by 1,4-hydride addition and protonation to achieve the nitroalkanes.

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