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A strategy for oxidative kinetic resolution of racemic indolines was developed, employing salicylaldehyde derivative as the pre-resolving reagent and chiral phosphoric acid as the catalyst. The iminium intermediate, formed by the condensation reaction of an enantiomer of indoline with salicylaldehyde derivative, was hydrogenated by the same enantiomer of indoline to afford another enantiomer of indoline by a self-redox mechanism. The oxidative kinetic resolution of 2-aryl-substituted indolines proceeded to give enantiomers in good yields with excellent enantioselectivities. [ABSTRACT FROM AUTHOR]

Abstract: The enantioselective hydrophosphonylation reaction of diisopropyl phosphite with aldimine furnished α-amino phosphonates with high enantioselectivities by means of a chiral phosphoric acid. DFT calculation of the effect of 3,3′-substituents of the phosphoric acid revealed the reason for the high enantioselectivities. [Copyright &y& Elsevier]

A variety of indoles underwent enantioselective Friedel–Crafts alkylation with α,β-unsaturated acyl phosphonates in the presence of 10 mol% chiral BINOL-based phosphoric acid and subsequent treatment with methanol and DBU to give methyl 3-(indol-3-yl)propanoates in good yields and with high enantioselectivities. [ABSTRACT FROM AUTHOR]

A novel chiral phosphoric acid bearing a biphenol backbone was synthesized and its catalytic activity was investigated in the enantioselective Mannich-type reaction of ketene silyl acetals with aldimines. [ABSTRACT FROM AUTHOR]

Reported herein is an enantiodivergent synthesis of chiral biaryls by a chiral phosphoric acid catalyzed asymmetric transfer hydrogenation reaction. Upon treatment of biaryl lactols with aromatic amines and a Hantzsch ester in the presence of chiral phosphoric acid, dynamic kinetic resolution (DKR) involving a reductive amination reaction proceeded smoothly to furnish both R and S isomers of chiral biaryls with excellent enantioselectivities by proper choice of hydroxyaniline derivative. This trend was observed in wide variety of substrates, and various chiral biphenyl and phenyl naphthyl adducts were synthesized with satisfactory enantioselectivities in enantiodivergent fashion. The enantiodivergent synthesis of synthetically challenging, chiral o-tetrasubstituted biaryls were also accomplished, and suggests high synthetic potential of the present method. [ABSTRACT FROM AUTHOR]

Reported herein is an enantiodivergent synthesis of chiral biaryls by a chiral phosphoric acid catalyzed asymmetric transfer hydrogenation reaction. Upon treatment of biaryl lactols with aromatic amines and a Hantzsch ester in the presence of chiral phosphoric acid, dynamic kinetic resolution (DKR) involving a reductive amination reaction proceeded smoothly to furnish both R and S isomers of chiral biaryls with excellent enantioselectivities by proper choice of hydroxyaniline derivative. This trend was observed in wide variety of substrates, and various chiral biphenyl and phenyl naphthyl adducts were synthesized with satisfactory enantioselectivities in enantiodivergent fashion. The enantiodivergent synthesis of synthetically challenging, chiral o-tetrasubstituted biaryls were also accomplished, and suggests high synthetic potential of the present method. [ABSTRACT FROM AUTHOR]

Described herein is a highly enantioselective synthesis of fused piperidine and pyrrolidine derivatives with all-carbon stereogenic centers. The enantioselective reductive amination from Cs-symmetric 1,3-dione derivatives proceeded in a highly stereoselective manner by taking advantage of the desymmetrization approach to afford fused heterocycles with contiguous stereogenic centers in good to excellent enantioselectivities (up to 98% ee). [ABSTRACT FROM AUTHOR]

By use of 2-deuterated benzothiazoline as a deuterium donor in combination with a chiral phosphoric acid, the transfer deuteration of ketimine and α-iminoester took place smoothly to give α-deuterated amines in high yields with excellent enantioselectivities. The remarkable kinetic isotope effect suggests that carbon–deuterium bond cleavage is the rate-determining step. [ABSTRACT FROM AUTHOR]

An abstract of the article "Enantioselective Synthesis of Fused Heterocycles with Contiguous Stereogenic Centers by Chiral Phosphoric Acid Catalyzed Symmetry Breaking" by Keiji Mori, Ayaka Miyake and Takahiko Akiyama is presented.

Asymmetric synthesis of tetrahydrobenzodiazepines was achieved by transfer hydrogenation of dihydrobenzodiazepines with benzothiazoline having a hydrogen-bonding donor substituent by means of a newly synthesized chiral phosphoric acid. This method was applicable to various racemic dihydrobenzodiazepines to give the corresponding products in good yields with excellent diastereoselectivities and enantioselectivities taking advantage of the dynamic kinetic resolution. Furthermore, the effect of bulky substituent at 3,3′-position on the catalyst and hydrogen-bonding donor substituent on benzothiazoline was fully elucidated by the theoretical study. [ABSTRACT FROM AUTHOR]

Friedel-Crafts alkylation of indoles by (Z)-nitroalkenes proceeds highly enantioselective in the presence of chiral phosphoric acid. [ABSTRACT FROM AUTHOR]

We report herein a highly enantioselective synthesis of multisubstituted biaryl chlorides/iodides by sequential halogenation reactions (desymmetrization/kinetic resolution sequence). The selectivity of biaryl chlorides/iodides obtained in the first asymmetric reaction (desymmetrization) could be enhanced by the kinetic resolution-type asymmetric bromination to afford the corresponding chiral biaryl chlorides/iodides in excellent selectivities (up to 99 % ee). [ABSTRACT FROM AUTHOR]

Chiral phosphoric acid catalyzed transfer hydrogenation of ketimines derived from propiophenone derivatives and reductive amination of alkyl ethyl ketone derivatives were extensively examined in the presence of two representative hydrogen donors. The excellent enantioselective transfer hydrogenation was achieved by use of benzothiazoline as a hydrogen donor. The theoretical studies elucidated that the unsymmetrical structure of benzothiazoline plays an important role in high enantioselective hydrogenation. [ABSTRACT FROM AUTHOR]

Dihydrobenzodiazepines or benzodiazepines bearing aryl substituents at the 2- and 4-position of the heterocyclic part are transformed to the chiral title compounds in the presence of BNPA using different amounts of the hydrogen transfer reagent BTA. [ABSTRACT FROM AUTHOR]

This new method proceeding via hydrogen transfer to imines by means of a chiral phosphoric acid catalyst is applicable to both 2-aryl and 2-alkyl substituted indolines. [ABSTRACT FROM AUTHOR]