With the rapid development of biomimetic asymmetric reduction, the demand for efficient chiral and regenerable NAD(P)H models is growing rapidly. Herein, a new class of 2.2paracyclophane-based chiral ...and regenerable NAD(P)H models (CYNAMs) was designed and synthesized. The first enantioselective biomimetic reduction of tetrasubstituted alkene flavonoids has been successfully realized through enzyme-like cooperative bifunctional activation, giving chiral flavanones with up to 99% yield and 99% ee.
With the rapid development of biomimetic asymmetric reduction, the demand for efficient chiral and regenerable NAD(P)H models is growing rapidly.
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IJS, KILJ, NUK, UL, UM, UPUK
The development of biomimetic chemistry based on the NAD(P)H with hydrogen gas as terminal reductant is a long‐standing challenge. Through rational design of the chiral and regenerable NAD(P)H ...analogues based on planar‐chiral ferrocene, a biomimetic asymmetric reduction has been realized using bench‐stable Lewis acids as transfer catalysts. A broad set of alkenes and imines could be reduced with up to 98 % yield and 98 % ee, likely enabled by enzyme‐like cooperative bifunctional activation. This reaction represents the first general biomimetic asymmetric reduction (BMAR) process enabled by chiral and regenerable NAD(P)H analogues. This concept demonstrates catalytic utility of a chiral coenzyme NAD(P)H in asymmetric catalysis.
Through rational design of chiral and regenerable NAD(P)H analogues based on planar‐chiral ferrocene, a biomimetic asymmetric reduction has been realized using bench‐stable Lewis acids as transfer catalysts. A broad set of tetrasubstituted alkenes and imines could be reduced with up to 98 % yield and 98 % ee. This protocol represents the first general biomimetic asymmetric reduction process enabled by NAD(P)H analogues.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
A novel transfer-catalyst-free biomimetic reduction of the tetrasubstituted olefins 3-sulfonyl coumarins with the chiral and regenerable 2.2paracyclophane-based NAD(P)H model CYNAM has been ...developed, affording chiral 3-sulfonyl dihydrocoumarins with excellent enantioselectivities.
A novel transfer-catalyst-free biomimetic reduction of 3-sulfonyl coumarins with the chiral and regenerable NAD(P)H model CYNAM has been developed, affording the 3-sulfonyl dihydrocoumarins with excellent enantioselectivities.
Compared with heteroarenes, homogeneous asymmetric hydrogenation of all‐carbon aromatic rings is a longstanding challenge in organic synthesis due to the strong aromaticity and difficult ...enantioselective control. Herein, we report the rhodium/diphosphine‐catalyzed asymmetric hydrogenation of all‐carbon aromatic rings, affording a series of axially chiral cyclic compounds with high enantioselectivity through desymmetrization or kinetic resolution. In addition, the central‐chiral cyclic compounds were also obtained by asymmetric hydrogenation of phenanthrenes bearing a directing group. The key to success is the introduction of chiral diphosphine ligands with steric hindrance and strong electron‐donating properties. The axially chiral monophosphine ligands could be obtained by simple conversion of the hydrogenation products bearing the phosphine atom.
The first rhodium/diphosphine‐catalyzed asymmetric hydrogenation of all‐carbon aromatic rings, anthracenes and naphthalenes, was reported, affording the axially chiral biaryl compounds by desymmetrization or kinetic resolution. Meanwhile, central‐chiral cyclic compounds were also obtained by asymmetric hydrogenation of phenanthrenes. In addition, after simple conversion of the products, the axially chiral monophosphine ligands could be obtained.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Reductive desymmetrization of achiral or meso diketones has attracted considerable attention due to these motifs which play important roles in organic synthesis, pharmaceuticals and functional ...materials. This review focuses on recent advances in homogeneous reductive desymmetrization of 1,2‐, 1,3‐ and 1,4‐diketones, which provides an efficient and practical access to structurally diverse chiral α‐, β‐ or γ‐hydroxy ketone derivatives.
Reductive desymmetrization of achiral or meso diketones has attracted considerable attention due to these motifs which play important roles in organic synthesis, pharmaceuticals and functional materials. This review focuses on recent advances in homogeneous reductive desymmetrization of 1,2‐, 1,3‐ and 1,4‐diketones, which provides an efficient and practical access to structurally diverse chiral α‐, β‐ or γ‐hydroxy ketone derivatives.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
An efficient access to optically active sulfahydantoins, 4-aryl-1,2,5-thiadiazolidin-3-one 1,1-dioxides, was developed through palladium-catalyzed asymmetric hydrogenation of the corresponding cyclic ...N-sulfonylketimines with up to 98% ee.
Because of the formidable development of the asymmetric reduction of tetrasubstituted olefins, an effective method is in urgent demand. Herein, through the biomimetic protocol of the coenzyme ...NAD(P)H, the reduction of tetrasubstituted olefin 2,3-substituted 1H-inden-1-ones has been successfully realized with the catalytic chiral NAD(P)H model CYNAM, which is hard to bring about via the common rhodium or iridium-based catalytic system, producing the corresponding products in good yield (up to 98%) with good enantioselectivity (up to 99% ee). Furthermore, the chiral bioactive molecule can be concisely synthesized from the reduced product.
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IJS, KILJ, NUK, PNG, UL, UM
The coenzyme NAD(P)H plays an important role in electron as well as proton transmission in the cell. Thus, a variety of NAD(P)H models have been involved in biomimetic reduction, such as ...stoichiometric Hantzsch esters and achiral regenerable dihydrophenantheridine. However, the development of a general and new-generation biomimetic asymmetric reduction is still a long-term challenge. Herein, a series of chiral and regenerable NAD(P)H models with central, axial, and planar chiralities have been designed and applied in biomimetic asymmetric reduction using hydrogen gas as a terminal reductant. Combining chiral NAD(P)H models with achiral transfer catalysts such as Brønsted acids and Lewis acids, the substrate scope could be also expanded to imines, heteroaromatics, and electron-deficient tetrasubstituted alkenes with up to 99% yield and 99% enantiomeric excess (ee). The mechanism of chiral regenerable NAD(P)H models was investigated as well. Isotope-labeling reactions indicated that chiral NAD(P)H models were regenerated by the ruthenium complex under hydrogen gas first, and then the hydride of NAD(P)H models was transferred to unsaturated bonds in the presence of transfer catalysts. In addition, density functional theory calculations were also carried out to give further insight into the transition states for the corresponding transfer catalysts.
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Biomimetic asymmetric reduction of 2-functionalized quinolines has been successfully developed with the chiral and regenerable NAD(P)H model CYNAM in the presence of transfer catalyst simple ...achiral phosphoric acids, providing the chiral 2-functionalized tetrahydroquinolines with up to 99% ee. Using this methodology as a key step, a chiral and potent opioid analgesic containing a 1,2,3,4-tetrahydroquinoline motif was synthesized with high overall yield.
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IJS, KILJ, NUK, PNG, UL, UM
In our previous work, we reported the synthesis of chiral and regenerable 2.2paracyclophane-derived NAD(P)H models CYNAMs and their application in biomimetic asymmetric reduction of tetrasubstituted ...olefins. Herein, the biomimetic asymmetric reduction of imines and heteroaromatics has been successfully achieved using the chiral and regenerable CYNAMs and simple achiral phosphoric acid as the transfer catalyst, providing the chiral amines with up to 99% yield and 99% ee.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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