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A new strategy for the enantioselective construction of chiral 2,3- cis-dimethyldihydrobenzofurans has been developed by a ruthenium-catalyzed asymmetric hydrogenation of racemic α-aryloxybutanone via dynamic kinetic resolution (DKR), combined with a palladium-catalyzed intramolecular reductive Heck cyclization. Starting from optically active 2,3- cis-dimethyldihydrobenzofuran, the natural products (+)/(−)-PI-220 and (+)-3- epi-furaquinocin C were synthesized in high yields. [ABSTRACT FROM AUTHOR]

An iridium complex with a newly prepared chiral spiro amino-phosphine ligand efficiently catalyzed the hydrogenation of both β-aryl-β-methyl-nitroalkenes and β-alkyl-β-methyl-nitroalkenes to the corresponding saturated nitroalkanes, which represents the first report of a chiral catalyst that exhibits high enantioselectivity for the challenging hydrogenation of β,β-dialkyl-nitroalkenes. [ABSTRACT FROM AUTHOR]

An iron-catalyzed asymmetric intramolecular cyclopropanation was realized in high yields and excellent enantioselectivity (up to 97 % ee) by using the iron complexes of chiral spiro-bisoxazoline ligands as catalysts. The superiority of iron catalysts exhibited in this reaction demonstrated the potential abilities of this sustainable metal in asymmetric carbenoid transformation reactions. [ABSTRACT FROM AUTHOR]

A highly enantioselective NH insertion reaction of α-diazoketones was developed by using cooperative catalysis by dirhodium(II) carboxylates and chiral spiro phosphoric acids. The insertion reaction provides a new access route to diverse chiral α-aminoketones, which are versatile building blocks in organic synthesis, with fast reaction rates, good yields and high enantioselectivity under mild and neutral conditions. [ABSTRACT FROM AUTHOR]

A palladium-catalyzed asymmetric OH insertion reaction was developed. Palladium complexes with chiral spiro bisoxazoline ligands promoted the insertion of α-aryl-α-diazoacetates into the OH bond of phenols with high yield and excellent enantioselectivity under mild reaction conditions. This palladium-catalyzed asymmetric OH insertion reaction provided an efficient and highly enantioselective method for the preparation of synthetically useful optically active α-aryl-α-aryloxyacetates. [ABSTRACT FROM AUTHOR]

High turnover: An highly efficient catalytic asymmetric hydrogenation of δ‐aryl‐δ‐ketoesters has been realized by using the chiral spiroiridium catalyst (R)‐1. Chiral 1,5‐diol products are obtained with excellent enantioselectivity and turnover numbers (TONs) as high as 100 000. TOF=turnover frequency. [ABSTRACT FROM AUTHOR]

Carbon–heteroatom bonds (C–X) are ubiquitous and are among the most reactive components of organic compounds. Therefore investigations of the construction of C–X bonds are fundamental and vibrant fields in organic chemistry. Transition-metal-catalyzed heteroatom–hydrogen bond (X–H) insertions via a metal carbene or carbenoid intermediate represent one of the most efficient approaches to form C–X bonds. Because of the availability of substrates, neutral and mild reaction conditions, and high reactivity of these transformations, researchers have widely applied transition-metal-catalyzed X–H insertions in organic synthesis. Researchers have developed a variety of rhodium-catalyzed asymmetric C–H insertion reactions with high to excellent enantioselectivities for a wide range of substrates. However, at the time that we launched our research, very few highly enantioselective X–H insertions had been documented primarily because of a lack of efficient chiral catalysts and indistinct insertion mechanisms. [ABSTRACT FROM AUTHOR]

A copper-catalyzed asymmetric O-H insertion of α-di�azo phosphonates with alcohols by using chiral spiro bisoxazoline ligands was developed. The insertion reaction exhibited good yields (up to 89%) with high enantioselectivities (up to 98% ee) and provided an efficient approach for synthesis of enantiomerically enriched α-alkoxy and hydroxy phosphonate derivatives starting from readily available materials. [ABSTRACT FROM AUTHOR]

Review: 91 refs. [ABSTRACT FROM AUTHOR]

Abstract: A copper-catalyzed asymmetric allylic oxidation of acyclic olefins has been developed. By using the complexes of copper and chiral spiro bisoxazoline ligands as catalysts, the oxidation of various acyclic olefins was accomplished with excellent regioselectivity (>20:1 in most cases) and up to 67% ee under mild reaction conditions, which represents one of the best results for the enantioselective allylic oxidation of acyclic olefins. [Copyright &y& Elsevier]

Abstract: A palladium-catalyzed asymmetric allylation of isatins with allylic alcohols as an allyl donor was developed by using chiral spiro phosphoramidite ligands. A variety of chiral tertiary homoallylic alcohols 3-allyl-3-hydroxy-2-oxindoles were prepared directly from allylic alcohols in one step with excellent yields and moderate enantioselectivities. This represents the first catalytic asymmetric allylation of ketones with allylic alcohol as the allylating agent. [Copyright &y& Elsevier]

A highly efficient asymmetric hydrogenation of α,β-unsaturated carboxylic acids with tetrasubstituted olefin catalyzed by chiral spiro iridium complexes has been developed for the preparation of chiral α-substituted carboxylic acids in excellent enantioselectivities (up to 99% ee). [ABSTRACT FROM AUTHOR]

The highly efficient asymmetric total syntheses of (−)-Δ8-tetrahydrocannabinol ((−)-Δ8-THC) (13 steps, 35%) and (−)-Δ9-tetrahydrocannabinol ((−)-Δ9-THC) (14 steps, 30%) have been developed by using ruthenium-catalyzed asymmetric hydrogenation of racemic α-aryl cyclic ketones via dynamic kinetic resolution and intramolecular SNAr cyclization. [ABSTRACT FROM AUTHOR]

A highly efficient one-pot process via a tandem reaction of catalytic asymmetric hydrogenation and oxa-Michael cyclization for the synthesis of 2,6-cis-disubstituted tetrahydropyrans has been developed (ee up to 99.9%, cis/trans-selectivity up to 99:1). This method provides a concise route to (−)-centrolobine (68.8% yield, three steps). [ABSTRACT FROM AUTHOR]

Abstract: A highly enantioselective rhodium-catalyzed hydrogenation of both (Z)- and (E)-β-arylenamides was developed by using monodentate chiral spiro phosphite and phosphine ligands, respectively. The hydrogenation reaction provides an efficient access to optically active β-arylisopropylamines, important building blocks for the synthesis of biologically active compounds. [Copyright &y& Elsevier]

Abstract: By using iridium catalyst based on chiral spiro phosphine–oxazoline ligands, the hydrogenation of α-arylcinnamic acids was accomplished under ambient pressure and low catalyst loading (as low as 0.01 mol %), providing useful 2,3-diarylpropionic acids in high yields with excellent enantioselectivities (up to 99% ee). A catalytic enantioselective synthesis of (S)-equol with the present hydrogenation reaction as a key step was accomplished starting from commercially available starting materials in six steps with 48.4% overall yield. [Copyright &y& Elsevier]

Abstract: A palladium-catalyzed asymmetric umpolung allylation reaction of imines with allylic alcohols has been developed. In the presence of chiral spiro phosphoramidite ligand 4, the allylation was accomplished with high yields and good enantioselectivities. The use of highly stable and easily available allylic alcohols instead of allylic metal reagents facilitated the preparation of chiral homoallylic amines. [ABSTRACT FROM AUTHOR]

The chiral ligands containing pyridinyl moieties and oxazolines bridged by disubstituted methylene 2–4 were prepared and they provided ee values 17–68% higher than unsubstituted analogues 1 in the palladium-catalyzed enantioselective allylic alkylation of 1,3-diphenyl-2-propenyl acetate with dimethyl malonate. [Copyright &y& Elsevier]

Abstract: An asymmetric synthesis of Silodosin was accomplished in high yield via catalytic hydrogenation of α,β-unsaturated carboxylic acid derivatives by using chiral catalyst Ir-SIPHOX, followed by Curtius rearrangement. [Copyright &y& Elsevier]

Total syntheses of the title compounds establishes the absolute configuration of naturally occurring PI-220 as (2S,3R). [ABSTRACT FROM AUTHOR]

This method provides access to Boc-protected β,γ-unsaturated α-amino acid esters with excellent yields and enantioselectivities. [ABSTRACT FROM AUTHOR]

The title reaction provides a new method for the synthesis of α-diaryl acetates such as (III), (V), and (VII) in good yields and with high enantioselectivities. [ABSTRACT FROM AUTHOR]

An abstract of the article "Development of Chiral Spiro P-N-S Ligands for Iridium-Catalyzed Asymmetric Hydrogenation of β-Alkyl-β-ketoesters" by D. H. Bao and colleagues is presented.

An abstract of the article "Enantioselective Iron-Catalyzed Intramolecular Cyclopropanation Reactions" by J.-J. Shen and colleagues is presented.

This is the first asymmetric N-H insertion of α-diazoketones giving α-aminoketones in good yields and with high enantioselectivities. [ABSTRACT FROM AUTHOR]

The carboxy-directed hydrogenation prohibits the isomerization of the terminal olefins, and realizes the chemoselective hydrogenation of various dienes. [ABSTRACT FROM AUTHOR]

Chemical formulas showing highly enantioselective S-H bond insertion cooperatively catalyzed by dirhodium complexes and chiral spiro phosphoric acids are presented.

The title methodology allows the preparation of chiral α-substituted carboxylic acids in excellent yields and enantioselectivities. [ABSTRACT FROM AUTHOR]

The synthetic value of this protocol is demonstrated by an efficient preparation of nipecotic acid (VI). [ABSTRACT FROM AUTHOR]