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Abstract: A highly regio‐ and enantioselective hydrogenation of challenging tetrasubstituted allenyl sulfones has been developed, affording chiral allylic sulfones in good yields with excellent regio‐ and enantioselectivities (up to 99 % yield and 99 % ee). This method provides an efficient and concise route to chiral allylic sulfones, thus offering an atom‐economic process with a wide range of potential applications in organic synthesis and medicinal chemistry. [ABSTRACT FROM AUTHOR]

A diversity-oriented synthetic strategy was developed for the total synthesis of kainoid amino acids, which led to the enantioselective synthesis of (−)-kainic acid and the first total synthesis of (+)-acromelic acid C. Rh(i)-catalyzed asymmetric enyne cycloisomerization served as the key reaction in this strategy for the rapid construction of highly functionalized lactam, and the resulting vinyl acetate moiety was further utilized as a versatile building block for the installation of both isopropylidene and 2-pyridone units existing in natural kainoids. [ABSTRACT FROM AUTHOR]

A succinct and efficient protocol was developed for the synthesis of chiral aromatic ketones via asymmetric hydrogenation of β,β-disubstituted enones with rhodium catalysts based on chiral bisphosphine thiourea ligands. A series of substrates (17 examples) was smoothly catalyzed to afford the corresponding chiral aromatic ketones in high conversions (＞99%) with excellent enantioselectivities (up to 96% ee). [ABSTRACT FROM AUTHOR]

We have successfully developed the asymmetric hydrogenation of β-silyl-α,β-unsaturated esters to prepare chiral 3-substituted-3-silylpropionic ester products catalyzed by rhodium/bisphosphine-thiourea (ZhaoPhos) with excellent results (up to 97% yield, >99% ee, 1500 TON). Moreover, our hydrogenation products can be efficiently converted to other important organic molecules, such as chiral ethyl ( R)-3-hydroxy-3-phenylpropanoate or ( R)-3-[dimethyl(phenyl)silyl]-3-phenylpropanoic acid. [ABSTRACT FROM AUTHOR]

A rhodium-catalyzed asymmetric hydrogenation of challenging tetrasubstituted β-acetoxy-α-enamido esters was developed, giving chiral β-acetoxy-α-amido esters in high yields with excellent enantioselectivities (up to ＞99% ee). The products could be easily transformed to β-hydroxy-α-amino acid derivatives which are valuable chiral building blocks and a novel route for the synthesis of droxidopa was also developed. [ABSTRACT FROM AUTHOR]

Asymmetric hydrogenation of various 3-substituted maleic anhydrides catalyzed by Rh/bisphosphine-thiourea (ZhaoPhos) under mild conditions was successfully developed. A wide range of 3-alkyl and 3-aryl maleic anhydrides were hydrogenated well to provide the desired products 3-substituted succinic anhydrides in one hour with excellent results (full conversions, up to 99% yield, 99% ee, 3000 TON). Importantly, we developed a creative and efficient synthetic route to construct the key intermediate of the hypoglycemic drug mitiglinide through our catalytic system. [ABSTRACT FROM AUTHOR]

An efficient rhodium-catalyzed asymmetric hydrogenation of α-amino acrylonitriles has been developed, affording α-acylamino nitriles with high yields and excellent enantioselectivities (up to 99% yield and ＞99% ee). This novel methodology provides an efficient and concise synthetic route to chiral α-amino nitriles, which are versatile intermediates in organic synthesis. [ABSTRACT FROM AUTHOR]

Asymmetric hydroformylation represents one of the most efficient routes for the preparation of chiral aldehydes from alkenes in the presence of syngas in a perfect atom-economic way. During the past few decades, a variety of chiral ligands have been developed for the asymmetric hydroformylation. However, only a few ligands exhibit good performance in terms of the regio- and enantioselectivities. Additionally, for the chiral ligands developed up to now, only limited substrates were tolerated and no examples have led to the application of the asymmetric hydroformylation reaction on a commercial scale due to several technical challenges. This account provides a brief introduction of the current efficient chiral ligands for asymmetric hydroformylation and the ongoing efforts we have made in this field. [ABSTRACT FROM AUTHOR]

We successfully extended our Rh/bisphosphine-thiourea (ZhaoPhos) catalytic system to asymmetric hydrogenation of α,β-unsaturated N-acylpyrazoles affording products with high yields and excellent enantioselectivities (up to 97% yield, 99% ee). The pyrazole moiety played an important role in providing H-bond acceptor sites, which is critical for achieving high reactivities and enantioselectivities. [ABSTRACT FROM AUTHOR]

Excellent enantioselectivities (up to 97 % ee) and diastereoselectivities (up to >99:1 d.r.) have been achieved in the desymmetrization of cyclopentenes by catalytic hydroformylation. This novel methodology provides an efficient and concise synthetic route to chiral cyclopentane carboxaldehydes. The key intermediate, (1 S,3 S)-(3-hydroxymethyl)cyclopentanol, for the synthesis of carbocyclic-ddA was obtained in three steps. [ABSTRACT FROM AUTHOR]

Asymmetric hydrogenation of unprotected NH imines catalyzed by rhodium/bis(phosphine)-thiourea provided chiral amines with up to 97 % yield and 95 % ee. 1H NMR studies, coupled with control experiments, implied that catalytic chloride-bound intermediates were involved in the mechanism through a dual hydrogen-bonding interaction. Deuteration experiments proved that the hydrogenation proceeded through a pathway consistent with an imine. [ABSTRACT FROM AUTHOR]

The direct route: A Rhodium‐catalyzed asymmetric hydrogenation method for the efficient synthesis of a broad range of chiral allylic amines and aliphatic amines from readily available materials was developed. A chiral Z‐allylic amine was obtained for the first time through a Rhodium–DuanPhos‐catalyzed asymmetric hydrogenation. TMS=Trimethylsilyl, cod=cyclooctadiene, TON=turnover number. [ABSTRACT FROM AUTHOR]

An efficient and highly regio- and enantioselective catalytic asymmetric hydrogenation of α,γ-dienamido esters to γ,δ-unsaturated amido esters has been achieved using Rh/TangPhos as the catalyst. A series of γ,δ-unsaturated amido acids were furnished in excellent yields with up to 99 % ee. This effective methodology was applied in the asymmetric synthesis of key intermediate of Ramipril, an ACE inhibitor. [ABSTRACT FROM AUTHOR]

Review: [52 refs. [ABSTRACT FROM AUTHOR]

Asymmetric hydrogenation of 4-substituted cyclic enamido esters catalyzed by a rhodium–TangPhos complex provides an efficient method for the synthesis of chiral 4-substituted oxazolinones with excellent yields and good enantioselectivities. The products are valuable chiral building blocks and the applications as chiral auxiliaries and pharmaceuticals are well-known. [ABSTRACT FROM AUTHOR]

Highlyregioselective andenantioselective asymmetric hydrogenation of cyclic dienamides catalyzedby an Rh-DuanPhos complex has been developed, which provides a readilyaccessible method for the synthesis of chiral cyclic allylic aminesin excellent enantioselectivities (up to 99% ee). The products arevaluable chiral building blocks and could be easily transformed tomultisubstituted cyclohexane derivatives. [ABSTRACT FROM AUTHOR]

An efficient and highly enantioselective catalytic asymmetric hydrogenation of β-acylamino nitroolefins has been realized by using Rh-TangPhos as the catalyst. A series of β-amino nitroalkane products, which are versatile intermediates in organic synthesis, were obtained with high yield and good enantioselectivity. [ABSTRACT FROM AUTHOR]

The highly linear-selective hydroaminomethylation of styrenes is very challenging. Herein, an efficient, highly chemoselective, and linear-selective hydroaminomethylation (l/b up to >99:1) of styrenes using Rh(nbd)2SbF6with a pyrrole-based 3,3′,5,5′-substituted tetraphosphorus ligand is documented. This is in sharp contrast to other available processes leading to branched amines and provides a novel atom economic approach to 3-arylpropylamines. [ABSTRACT FROM AUTHOR]

A novel rhodium catalytic system with Naphos as ligand was developed for an efficient hydroaminomethylation of 1,1-diphenylethene under relatively mild conditions. This will allow for an atom-economic and environmentally benign synthesis of fenpiprane and related pharmaceuticals. [ABSTRACT FROM AUTHOR]

Abstract: The rhodium-catalyzed asymmetric hydrogenation of β-acetylamino acrylonitriles was investigated by using monophosphine and bisphosphine ligands. It was found that an Rh-QuinoxP∗ complex exhibited high enantioselectivities for β-aryl substituted β-acetylamino acrylonitriles and the Rh-JosiPhos CyPF-t-Bu complex was proven to be effective for the hydrogenation of tetrasubstituted olefins from cyclic β-acetylamino acrylonitriles. [Copyright &y& Elsevier]

Abstract: A new electron-rich TunePhos type ligand has been synthesized; excellent enantioselectivities (up to 99% ee) have been achieved in Rh-catalyzed asymmetric hydrogenation of α-dehydroamino acid methyl esters and dimethyl itaconate. [Copyright &y& Elsevier]

Abstract: Rhodium-catalyzed hydroformylation of 1,5-hexadiene to corresponding dialdehydes was investigated using tetraphosphorus ligands. These ligands showed a high regioselectivity for linear aldehydes (linear to branch ratio up to 98%) in very good yield (up to 87%). It was found that the introduction of the substituents at the ortho position of the biphenyl moiety has little effect on the regioselectivity and the electron-donating substituents retard the reaction somewhat. [Copyright &y& Elsevier]

The reaction tolerates diaryl as well as dialkyl substituted alkynes. [ABSTRACT FROM AUTHOR]

For the first time, a strategy for the enantioselective Rh-TaniaPhos catalyzed asymmetric hydrogenation of unprotected β-enamine phosphonates directly to free β-amino phosphonates is reported which occurs with high yields and good enantioselectivities (up to 86% ee). [ABSTRACT FROM AUTHOR]

Efficient asymmetric hydrogenation of α-dehydroamino ketones is achieved in excellent enantioselectivity using a Rh-DuanPhos catalyst. [ABSTRACT FROM AUTHOR]

Cyclic enamido esters undergo asymmetric hydrogenation in the presence of the optically active rhodium catalyst (RCT) to form 2-oxazolidinones in excellent yields with good enantioselectivities. [ABSTRACT FROM AUTHOR]

A graphical abstract of the article "Rhodium Catalyzed Asymmetric Hydrogenation of 2-Pyridine Ketones" is presented.

The methodology provides valuable building blocks for the synthesis of biologically active compounds which is exemplified by the transformation of one product into the corresponding α-hydroxy-β-amino acid, an intermediate of the taxol side chain. [ABSTRACT FROM AUTHOR]

Mild conditions, broad substrate scope, and the commercially available Rh-DuanPhos catalyst are features of this hydrogenation. [ABSTRACT FROM AUTHOR]

Due to NEt3 mediated isomerization also mixtures of α,β- and β,γ-unsaturated nitroalkenes can be deployed in this reaction. [ABSTRACT FROM AUTHOR]

In contrast to other known methods the linear products are predominantly formed by this procedure. [ABSTRACT FROM AUTHOR]

An abstract of the article "Rhodium-Catalyzed Asymmetric Hydroformylation of 1,1-Disubstituted Allylphthalimides: A Catalytic Route to β3-Amino Acids" by X. Zheng and colleagues is presented.