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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]

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]

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]

The high-yield reduction of aromatic ketimines into amines by using a novel catalyst based on a metallacarborane structure, 8,8'-μ-phosphate[(1,2-dicarba-closo-undecaborane)-3,3'-cobalt(- 1)(1',2'-dicarba-closo-undecaborane)] acid, is described. [ABSTRACT FROM AUTHOR]

A good mix: The title reaction of o‐alkynylacetophenones with the Hantzsch ester in the presence of a chiral copper/phosphate catalyst proceeds in good yields with excellent enantioselectivities. The key intermediate for enantiocontrol is the ion pair of the carbonyl ylide with a chiral phosphate anion, and this process provides straight forward access to highly enantioriched chiral isochromenes. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Phosphoric Acid Bridged Cobalt Bis(dicarbollide) Ion as a Highly Efficient Catalyst for the Organocatalytic Hydrogenation of Ketimines" by T. Akiyama and others, published in the journal "Synlett" in 2014.

The chiral phosphoricacid catalyzed enantioselective transferhydrogenation of various ketimines was achieved by the use of 2-arylindoline as the hydrogen donor. Corresponding chiral amines were obtainedin good chemical yields with excellent enantioselectivities. [ABSTRACT FROM AUTHOR]

Abstract: An efficient and practical protocol for the reduction of aldimines, ketimines, and α-imino esters in the presence of catalytic amount of molecular iodine with Hantzsch ester at ambient temperature afforded the corresponding amines in excellent yields. [Copyright &y& Elsevier]

The method is highly chemoselective and applied to the reduction of a wide range of sulfides, including benzyl and alkyl sulfides, and dithianes. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Asymmetric Transfer Hydrogenation of Ketimines by Indoline as Recyclable Hydrogen Donor" by K. Saito and colleagues, published in the "ChemInform" journal in 2014.

The asymmetricreduction of ketimines is animportant method for the preparation of amines in optically pure form.Inspired by the biological system using NAD(P)H, Hantzsch ester hasbeen extensively employed as a hydrogen donor in combination withchiral phosphoric acid for the transfer hydrogenation of ketiminesto furnish amines with high to excellent enantioselectivities. [ABSTRACT FROM AUTHOR]

A facile protocol using molecular iodine as the catalyst and Hantzsch ester as hydrogen source allows the conversion of aldimines, ketimines and α-imino esters into the corresponding amines under mild reaction conditions. [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]

Review: 62 refs. [ABSTRACT FROM AUTHOR]

It is demonstrated that asymmetric hydrogenation of ketimines can be advantageously achieved with benzothiazoline as hydrogen donor in the presence of a chiral BINOL derived phosphonic acid as catalyst. [ABSTRACT FROM AUTHOR]

The article presents chemical equations on the article "Enantioselective Transfer Hydrogenation of Difluoromethyl Ketimines Using Benzothiazoline as a Hydrogen Donor in Combination with a Chiral Phosphoric Acid" by T. Sakamoto and others, published in the "Journal of Organic Chemistry."

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]