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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]

The hydrogenation of esters catalyzed by a manganese complex of phosphine‐aminopyridine ligand was developed. Using this protocol, a variety of (hetero)aromatic and aliphatic carboxylates including biomass‐derived esters and lactones were hydrogenated to primary alcohols with 63–98% yields. The manganese catalyst was found to be active for the hydrogenation of methyl benzoate, providing benzyl alcohol with turnover numbers (TON) as high as 45,000. Investigation of catalyst intermediates indicated that the amido manganese complex was the active catalyst species for the reaction. [ABSTRACT FROM AUTHOR]

A scalable enantioselective total synthesis of (−)‐goniomitine has been developed by using an iridium‐catalyzed asymmetric hydrogenation of an exocyclic enone ester to control the configuration of the molecule. The synthesis begins from commercially available starting materials, and proceeds through an integrated asymmetric ketone hydrogenation, Johnson–Claisen rearrangement, and one‐pot oxidation/deprotection/cyclization process. With this highly efficient and scalable strategy, (−)‐goniomitine was synthesized in eleven steps with 27 % overall yield, and formal enantioselective syntheses of (+)‐1,2‐dehydroaspidospermidine, (+)‐aspidospermidine, and (+)‐vincadifformine were also achieved. Going, going, goniomitine: A scalable enantioselective synthetic strategy featuring an iridium‐catalyzed asymmetric hydrogenation of an exocyclic enone ester for the total synthesis of (−)‐goniomitine and formal syntheses of (+)‐1,2‐dehydroaspidospermidine, (+)‐aspidospermidine, and (+)‐vincadifformine is reported. [ABSTRACT FROM AUTHOR]

The hydrogenation of amides to amines has been developed by using the catalyst [Ru(H)2(CO)(Triphos)] (Triphos=1,1,1-tri(diphenylphosphinomethyl)ethane) and catalytic boron Lewis acids such as B(C6F5)3 or BF3 ⋅Et2O as additives. The reaction provides an efficient method for the preparation of secondary amines from amides in good yields with high selectivity. [ABSTRACT FROM AUTHOR]

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]

A ruthenium complex with a tetradentate bipyridine ligand was proved to be a highly efficient catalyst for the conversions of CO2. Turnover numbers up to 300 000, 9800, and 2100 were achieved for the hydrogenations of CO2 to formamides, formamides to methanol and amines, and the direct hydrogenation of CO2 to methanol, respectively. A ruthenium catalyst with tetradentate bipyridine ligand gave TONs up to 300 000, 9800, and 2100 for the hydrogenations of CO2 to formamides, formamides to methanol and amines, and the direct hydrogenation of CO2 to methanol, respectively. [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]

Inspir(o)ierend: Eine effiziente katalytische asymmetrische Hydrierung von δ ‐ Aryl ‐ δ ‐ ketoestern gelang mit dem chiralen Spiroiridium ‐ Katalysator (R) ‐ 1. Die chiralen 1,5 ‐ Diolprodukte entstanden mit exzellenter Enantioselektivität bei Umsatzzahlen (TONs) bis 100 000. TOF=Umsatzfrequenz. [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]

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 asymmetric hydrogenation of α-substituted α,β-unsaturated acyclic ketones catalyzed by chiral spiro iridium complexes for the preparation of chiral 2-substituted allylic alcohols has been developed (ee up to 99.7%). This method provides a concise route to (−)-mesembrine (34% yield, 12 steps). [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]

A highly efficient catalytic method for hydrogenation of biomass-derived levulinic acid has been developed and the iridium trihydride complexes of PNP pincer ligands were found to be extremely active catalysts for this transformation, providing γ-valerolactone in high yields with TONs as high as 71 000. [ABSTRACT FROM AUTHOR]

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]

Review: 91 refs. [ABSTRACT FROM AUTHOR]

Review: [71 refs. [ABSTRACT FROM AUTHOR]

The catalytic hydrogenation of α-keto acids employing an Ir/SpiroPAP (IRC) catalyst proceeds under mild conditions with potential application on large scale synthesis. [ABSTRACT FROM AUTHOR]

Reaction is successfully applied in the synthesis of drugs (R)-clorprenaline (VII) (β2-agonist) and (R)-phenylephrine (VIII) (α-adrenergic receptor agonist). [ABSTRACT FROM AUTHOR]

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

This method yields the title compounds in high yields and with excellent enantioselectivities under mild reaction conditions and with low catalyst loadings. [ABSTRACT FROM AUTHOR]

This method uses catalyst loadings as low as 0.1 mol% and yields (cis,cis)-reaction products in good yields and with high enantio- and diastereoselectivities. [ABSTRACT FROM AUTHOR]

The spiro pyridine-aminophosphine catalyst ligands (I) are successfully applied in the title reaction to afford the alcohol products with excellent enantioselectivity. [ABSTRACT FROM AUTHOR]

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]

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]