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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]

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]

Spiral binding: A highly enantioselective hydrogenation of unsaturated heterocyclic acids has been developed by using chiral iridium/spirophosphino oxazoline catalysts (see scheme; BArF−=tetrakis[3,5‐bis(trifluoromethyl)phenyl]borate, Boc=tert‐butoxycarbonyl). This reaction provided an efficient method for the preparation of optically active heterocyclic acids with excellent enantioselectivities. [ABSTRACT FROM AUTHOR]

An efficient catalytic asymmetric hydrogenation of racemic α-arylcyclohexanones with an ethylene ketal group at the 5-position of the cyclohexane ring via dynamic kinetic resolution has been developed, giving chiral α-arylcyclohexanols with two contiguous stereocenters with up to 99% ee and >99:1 cis/ trans-selectivity. Using this highly efficient asymmetric hydrogenation reaction as a key step, (−)-α-lycorane was synthesized in 19.6% overall yield over 13 steps from commercially available starting material. [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]

A concise and efficient strategy has been developed to construct a polyketide chain by employing relay asymmetric hydrogenations catalyzed by two chiral spiro iridium catalysts. By using this strategy, an enantioselective total synthesis of (−)‐doliculide has been achieved in 19 steps with 6.9 % overall yield. The route features high enantioselectivity and diastereoselectivity. The catalyst loading can be as low as 0.005 mol‐%. It is convenient to obtain natural polyketides and their analogues by this strategy. [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]

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

The carboxy group in the substrates is crucial for this reaction as it acts as an anchor for the Ir-catalysts. [ABSTRACT FROM AUTHOR]

The reaction is carried out in the presence of phosphine PHL-1 and phosphite PHL-2 to produce both enantiomers of the desired amines, building blocks of natural products, form either (E)- or (Z)-substrates. [ABSTRACT FROM AUTHOR]

The title compounds (II) are obtained by asymmetric hydrogenation of α-oxymethylcinnamic acids using chiral spiro phosphine-oxazoline/iridium complexes as catalysts. [ABSTRACT FROM AUTHOR]

Saturated nitroalkanes are prepared by asymmetric hydrogenation of nitroalkenes using iridium complexes with a newly prepared chiral spiro aminophosphine ligand as catalyst. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Highly Efficient and Practical Hydrogenation of Olefins Catalyzed by in situ Generated Iron Complex Catalysts" published in the periodical "Organic Chemistry Frontiers" in 2015.

A substituent adjacent to the pyridine N atom is crucial to block the coordination ability of the pyridine moiety, an effect which is evidently overturned by the proximate second N atom in substrate (Vb). [ABSTRACT FROM AUTHOR]