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Comprehensive Summary: The design and synthesis of spirochroman‐2‐on‐4,1'‐indan‐7'‐ol (SCIOL) and its application for synthesizing chiral monophosphinite ligands are reported. The synthesis features a tandem double Friedel‐Crafts reaction/lactonization to construct the spiro framework and the desired racemic SCIOL was obtained via 6 steps with a total yield of 44.5%. Using an inclusion resolution with N‐benzylcinchonidinium chloride, the optical SCIOL could be obtained in good yields on a gram scale. The preliminary studies indicated that the corresponding chiral spiro monophosphinite ligands exhibit high catalytic activity and enantioselectivity (up to 94% ee) in the rhodium‐catalyzed asymmetric hydrogenation of N‐acetyl dehydroamino esters. These outcomes highlight the significant potential of SCIOL as a useful framework for the development of chiral spiro ligands. [ABSTRACT FROM AUTHOR]

Manganese complexes with tridentate PNN ligands have been synthesized as catalysts for hydrogenative cross‐coupling reaction of nitriles and amines to form secondary imines. This reaction afforded a variety of unsymmetrical secondary imines in good yields with excellent selectivity. Investigation of catalyst intermediates indicated that an amido manganese complex may be the active catalyst species for this reaction. [ABSTRACT FROM AUTHOR]

The chiral tridentate spiro P-N-S ligands (SpiroSAP) were developed, and their iridium complexes were prepared. Introduction of a 1,3-dithiane moiety into the ligand resulted in a highly efficient chiral iridium catalyst for asymmetric hydrogenation of β-alkyl-β-ketoesters, producing chiral β-alkyl-β-hydroxyesters with excellent enantioselectivities (95-99.9 % ee) and turnover numbers of up to 355 000. [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]

An asymmetric hydrogenation of α-oxymethylcinnamic acids was developed by using chiral spiro phosphine-oxazoline/iridium complexes as catalysts to prepare β2-hydroxycarboxylic acids with high reactivity (TON up to 2000) and excellent enantioselectivity (up to 99.5% ee). By using this highly efficient asymmetric hydrogenation as a key step, a concise total synthesis of natural product homoisoflavone ( S)-(+)- 4 was accomplished. [ABSTRACT FROM AUTHOR]

Highly efficient iridium catalyzed asymmetric transfer hydrogenation of simple ketones with ethanol as a hydrogen donor has been developed. By using chiral spiro iridium catalysts (S)-1a a series of alkyl aryl ketones were hydrogenated to chiral alcohols with up to 98% ee. [ABSTRACT FROM AUTHOR]

The article discusses the progresses in the study of transition-metal catalysis and organocatalysis. Topics covered include the importance of catalysis to modern synthetic chemistry and the expansion of the global catalysis market through time. Also mentioned is the focus of catalysis on the modification of ligands and transition metal catalysts.

Comprehensive Summary: The design and synthesis of spirochroman‐2‐on‐4,1'‐indan‐7'‐ol (SCIOL) and its application for synthesizing chiral monophosphinite ligands are reported. The synthesis features a tandem double Friedel‐Crafts reaction/lactonization to construct the spiro framework and the desired racemic SCIOL was obtained via 6 steps with a total yield of 44.5%. Using an inclusion resolution with N‐benzylcinchonidinium chloride, the optical SCIOL could be obtained in good yields on a gram scale. The preliminary studies indicated that the corresponding chiral spiro monophosphinite ligands exhibit high catalytic activity and enantioselectivity (up to 94% ee) in the rhodium‐catalyzed asymmetric hydrogenation of N‐acetyl dehydroamino esters. These outcomes highlight the significant potential of SCIOL as a useful framework for the development of chiral spiro ligands. [ABSTRACT FROM AUTHOR]

Abstract: A selective oxidation of benzylic C(sp3)–H bonds to C(sp3)–O bonds catalyzed by copper complexes of quinoline–imine ligands was developed with peresters as oxidants under mild reaction conditions, which converted benzylic methylenes directly into benzylic alcohols and esters by means of direct C–H bond functionalization. [Copyright &y& Elsevier]

Abstract: Palladium complexes of chiral spiro phosphoramidite and phosphite ligands are effective catalysts in the asymmetric hydrovinylation of vinylarenes with ethylene. The hydrovinylation products were obtained in modest selectivity with enantioselectivities up to 92% ee. The structures of the palladium catalysts have been analyzed by X-ray diffraction. The active catalyst contained one monodentate ligand. A kinetic resolution accompanied the isomerization of the hydrovinylation product in the reaction. [Copyright &y& Elsevier]

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]

Abstract: Two novel chiral spiro nitrogen-containing ligands, 7,7′-bis(2-pyridinecarboxamido)-1,1′-spirobiindane (abbreviated as SIPAD) and 7,7′-bis(2-quinolinecarboxamido)-1,1′-spirobiindane (abbreviated as SIQAD), were conveniently prepared from 1,1′-spirobiindane-7,7′-dicarboxylic acid in high yields (85% and 84%, respectively) in two steps. The cobalt complexes prepared in situ from Co(OAc)2 and the ligands have been proven to be efficient catalysts for the asymmetric Michael addition reaction of malonates to chalcone derivatives. The alkylation products were obtained in high yields with moderate enantiomeric excesses under mild reaction conditions. [Copyright &y& Elsevier]

Abstract: A new type of triaryl phosphine-functionalized imidazolium salts 6 were prepared. Their palladium complexes, generated in situ, were successfully applied in the palladium-catalyzed Heck reaction. Using 1mol% of Pd(dba)2 and 1mol% 6c in the presence of 2equiv of K2CO3 in DMAc has proven to be highly efficient for the coupling of a wide array of aryl bromides and iodides with acrylates in excellent yield. The coupling of 4-bromotoluene with various styrene derivatives catalyzed by Pd/6c complex also gave good results. [Copyright &y& Elsevier]

New mono dentate chiral phosphonites were synthesized from enantiomerically pure 1,1'-spirobiindane- 7,7'-diol. The phosphonites 2 were efficient ligands for the Rh-catalyzed asymmetric hydrogenation of α- and β-dehydroamino acid derivatives, providing the amino acids in high enantioselectivities. The study of electronic effect showed that the electron-withdrawing substitutent on the P-phenyl ring of the phosphonite ligand dramatically decreased both the reactivity and enantioselectivity of the ligand. [ABSTRACT FROM AUTHOR]

Asymmetric hydrosilylation of styrene derivatives with trichlorosilane in the presence of palladium complexes of chiral spiro phosphoramidites provided 1-aryl-1-silylalkanes as single regioisomers in high yields, which have been oxidized with hydrogen peroxide to give the corresponding chiral alcohols in up to 99.1% ee. [Copyright &y& Elsevier]

Three chiral 4,4′-substituted 1,1′-spirobiindane-7,7′-diols and related monodentate spiro phosphoramidite ligands have been readily synthesized from enantiomerically pure 1,1′-spirobiindane-7,7′-diol. Excellent enantioselectivities were obtained with these new ligands in the rhodium-catalyzed asymmetric hydrogenation of dehydroamino acid derivatives and enamides. Comparing SIPHOS, ligands 4,4′-dibromo-SIPHOS and 4,4′-diphenyl-SIPHOS gave similarly high enantioselectivities although the rates in hydrogenations of enamides are somewhat slower. Methoxy substituents at the 4,4′-position of ligands slightly reduced enantioselectivities of hydrogenation reactions. [Copyright &y& Elsevier]

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]

The chiral spirobiindane ligand, 1,1′-spirobiindane-7,7′-diol has been resolved efficiently by inclusion complexation with commercially available N-benzylcinchonidinium chloride. The resolved complex was studied by X-ray crystallography in order to characterize the intermolecular interactions and recognition nature. [Copyright &y& Elsevier]

Enantiomerically pure tetradentate bis(oxazolinyl)bipyridine ligands 1 have been synthesized in high yields. X-Ray analysis showed that the copper(I) complexes of ligands 1 had a C2-symmetric helical structure. Ruthenium complexes of ligands 1 prepared in situ were found to be efficient in the asymmetric cyclopropanation of styrene with ethyl diazoacetate. [Copyright &y& Elsevier]

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.

Chiral alcohols [(II) and (IV)] are simply and efficiently synthesized with up to 98% e.e. [ABSTRACT FROM AUTHOR]

A new type of readily available, air-stable Ru-complex is described. [ABSTRACT FROM AUTHOR]

The cyclization of various diazo ester substrates in the presence of the optimal ligands (Sa)-INH and (Sa)-IOP is advantageous with regards to high yields, excellent enantioselectivity, and wide substrate scope. [ABSTRACT FROM AUTHOR]