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 facile access to optically active cyclic ureas was developed through palladium‐catalyzed asymmetric hydrogenation of pyrimidines containing tautomeric hydroxy group with up to 99 % ee. Mechanistic ...studies indicated that reaction pathway proceed through hydrogenation of C=N of the oxo tautomer pyrimidin‐2(1H)‐one, acid‐catalyzed isomerization of enamine–imine, and hydrogenation of imine pathway. In addition, the chiral cyclic ureas are readily converted into useful chiral 1,3‐diamine and thiourea derivatives without loss of optical purity.
Introducing asymmetry: An enantioselective palladium‐catalyzed hydrogenation of pyrimidines containing a tautomeric hydroxy group is described. This methodology provides a convenient route to chiral cyclic ureas with up to 99 % ee. The cyclic chiral ureas are readily converted into useful chiral 1,3‐diamine and thiourea derivatives without loss of optical purity.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
A palladium‐catalyzed enantioselective CH functionalization of indoles was achieved with an axially chiral 2,2′‐bipyridine ligand, thus providing the desired indol‐3‐acetate derivatives with up to ...98 % ee. Moreover, the reaction protocol was also effective for asymmetric OH insertion reaction of phenols using α‐aryl‐α‐diazoacetates. This represents the first successful application of bipyridine ligands with axial chirality in palladium‐catalyzed carbene migratory insertion reactions.
Get the axial: The title reaction involving diazo compounds was achieved with an axially chiral 2,2′‐bipyridine ligand. Moreover, insertion into OH bonds of phenols was also realized with up to 99 % ee by using this catalytic system.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
An efficient kinetic resolution of axially chiral 5- or 8-substituted quinoline derivatives was developed through asymmetric transfer hydrogenation of heteroaromatic moiety, simultaneously obtaining ...two kinds of axially chiral skeletons with up to 209 of selectivity factor. This represents the first successful application of asymmetric transfer hydrogenation of heteroaromatics in kinetic resolution of axially chiral biaryls.
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IJS, KILJ, NUK, PNG, UL, UM
A highly enantioselective synthesis of chiral fluorinated propargylamines was developed through phosphoric acid and ruthenium-catalyzed chemoselective biomimetic hydrogenation of the carbon–nitrogen ...double bond of fluorinated alkynyl ketimines in the presence of a carbon–carbon triple bond. This reaction features high chemoselectivity and slow background reaction. In addition, selective transformations of the chiral fluorinated propargylamines were also reported.
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Asymmetric hydrogenation: The title reaction provides an efficient and rapid access to chiral 1‐ and 3‐substituted 1,2,3,4‐tetrahydroisoquinolines with excellent enantioselectivity (see scheme; ...L=ligand). A preliminary mechanistic study indicates that the 1,2‐hydride addition might be the initial step in the reaction. The method has been used in the synthesis of urinary antispasmodic drug (+)‐solifenacin.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
A streamlined method for the enantioselective synthesis of 2-amino-4H-chromenes from readily available 2-alkyl-substituted phenols and active methylene compounds bearing a cyano group with up to 97% ...ee is presented. This reaction is a cascade procedure including manganese dioxide mediated C–H oxidation for the generation of o-quinone methides and bifunctional squaramide-catalyzed Michael addition/cyclization.
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An efficient method was developed for the alkylation of 2‐arylquinazolin‐4(3H)‐ones with cyclopropanols. The desired products β‐aryl ketones bearing the quinazolin‐4(3H)‐one scaffold were synthesized ...by Rh(III)‐catalyzed C−H activation of arenes and C−C cleavage of cyclopropanols. This method has a wide range of benzyl/phenyl substrate applicability and provides a theoretical guidance for our research to study quinazoline compounds.
An efficient method was developed for the alkylation of 2‐arylquinazolin‐4(3H)‐ones with cyclopropanols. The desired products β‐aryl ketones bearing the quinazolin‐4(3H)‐one scaffold were synthesized by Rh(III)‐catalyzed C−H activation of arenes and C−C cleavage of cyclopropanols. This method has a wide range of substrate applicability and provides a theoretical guidance for our research to study quinazoline compounds.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Using ureas as transfer catalysts through hydrogen bonding activation, biomimetic asymmetric reduction of benzoxazinones and quinoxalinones with chiral and regenerable NAD(P)H models was described, ...giving chiral dihydrobenzoxazinones and dihydroquinoxalinones with high yields and excellent enantioselectivities. A key dihydroquinoxalinone intermediate of a BRD4 inhibitor was synthesized using biomimetic asymmetric reduction.
Using ureas as transfer catalysts through hydrogen bonding activation, biomimetic asymmetric reduction of benzoxazinones and quinoxalinones has been developed, giving chiral products with high enantioselectivities. A key dihydroquinoxalinone intermediate of a BRD4 inhibitor was synthesized using biomimetic asymmetric reduction.
