Category: 139139-86-9

Aida, Yukimasa; Sugiyama, Haruki; Uekusa, Hidehiro; Shibata, Yu; Tanaka, Ken published the artcile< Rhodium-Catalyzed Asymmetric [2 + 2 + 2] Cycloaddition of α,ω-Diynes with Unsymmetrical 1,2-Disubstituted Alkenes>, Computed Properties of 139139-86-9, the main research area is rhodium catalyzed asym cycloaddition diyne unsym alkene; axial chiral biaryl phosphine rhodium complex cycloaddition catalyst; multicyclic compound enantioselective preparation.

It has been established that a cationic rhodium(I)/axially chiral biaryl bisphosphine complex catalyzes the asym. [2 + 2 + 2] cycloaddition of α,ω-diynes with electron-rich and unstrained unsym. 1,2-disubstituted alkenes to give chiral multicyclic compounds with good yields and ee values. Interestingly, enantioselectivity highly depends on the structures of α,ω-diynes used presumably due to the presence of two distinct reaction pathways.

Organic Letters published new progress about [2+2+2] Cycloaddition reaction (stereoselective). 139139-86-9 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Computed Properties of 139139-86-9.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Tanaka, Ken; Otake, Yousuke; Sagac, Hiromi; Noguchi, Keiichi; Hirano, Masao published the artcile< Highly regio-, diastereo-, and enantioselective [2 + 2 + 2] cycloaddition of 1,6-enynes with electron-deficient ketones catalyzed by a cationic RhI/H8-binap complex>, Computed Properties of 139139-86-9, the main research area is enyne stereoselective cyclocondensation keto ester amide diketone; rhodium BINAP regioselective diastereoselective enantioselective cycloaddition ortho functionalization; pyran dihydro heterocycle fused regioselective stereoselective preparation; ketone aryl ortho functionalization enyne rhodium catalyst.

A cationic RhI/H8-binap complex catalyzed regio-, diastereo-, and enantioselective [2 + 2 + 2] cycloaddition of 1,6-enynes with electron-deficient ketones to form fused dihydropyrans containing two quaternary carbon centers, e.g., I, is reported. Electron-rich aryl ketones react with 1,6-enynes in the presence of the same catalyst to give ortho-functionalized aryl ketones with excellent regio- and enantioselectivity.

Angewandte Chemie, International Edition published new progress about Alkenynes Role: RCT (Reactant), SPN (Synthetic Preparation), RACT (Reactant or Reagent), PREP (Preparation) (1,6-). 139139-86-9 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Computed Properties of 139139-86-9.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Duan, Ying; Li, Lu; Chen, Mu-Wang; Yu, Chang-Bin; Fan, Hong-Jun; Zhou, Yong-Gui published the artcile< Homogeneous Pd-Catalyzed Asymmetric Hydrogenation of Unprotected Indoles: Scope and Mechanistic Studies>, Electric Literature of 139139-86-9, the main research area is homogeneous palladium catalyzed asym hydrogenation unprotected indole.

An efficient palladium-catalyzed asym. hydrogenation of a variety of unprotected indoles has been developed that gives up to 98% ee using a strong Bronsted acid as the activator. This methodol. was applied in the facile synthesis of biol. active products containing a chiral indoline skeleton. The mechanism of Pd-catalyzed asym. hydrogenation was investigated as well. Isotope-labeling reactions and ESI-HRMS proved that an iminium salt formed by protonation of the C=C bond of indoles was the significant intermediate in this reaction. The important proposed active catalytic Pd-H species was observed with 1H NMR spectroscopy. It was found that proton exchange between the Pd-H active species and solvent trifluoroethanol (TFE) did not occur, although this proton exchange had been previously observed between metal hydrides and alc. solvents. D. functional theory calculations were also carried out to give further insight into the mechanism of Pd-catalyzed asym. hydrogenation of indoles. This combination of exptl. and theor. studies suggests that Pd-catalyzed hydrogenation goes through a stepwise outer-sphere and ionic hydrogenation mechanism. The activation of hydrogen gas is a heterolytic process assisted by trifluoroacetate of Pd complex via a six-membered-ring transition state. The reaction proceeds well in polar solvent TFE owing to its ability to stabilize the ionic intermediates in the Pd-H generation step. The strong Bronsted acid activator can remarkably decrease the energy barrier for both Pd-H generation and hydrogenation. The high enantioselectivity arises from a hydrogen-bonding interaction between N-H of the iminium salt and oxygen of the coordinated trifluoroacetate in the eight-membered-ring transition state for hydride transfer, while the active chiral Pd complex is a typical bifunctional catalyst, effecting both the hydrogenation and hydrogen-bonding interaction between the iminium salt and the coordinated trifluoroacetate of Pd complex. Notably, the Pd-catalyzed asym. hydrogenation is relatively tolerant to oxygen, acid, and water.

Journal of the American Chemical Society published new progress about Acid catalysis (strong Bronsted acids as activators). 139139-86-9 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Electric Literature of 139139-86-9.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Kim, In Su; Ngai, Ming-Yu; Krische, Michael J. published the artcile< Enantioselective Iridium-Catalyzed Carbonyl Allylation from the Alcohol or Aldehyde Oxidation Level via Transfer Hydrogenative Coupling of Allyl Acetate: Departure from Chirally Modified Allyl Metal Reagents in Carbonyl Addition>, Application In Synthesis of 139139-86-9, the main research area is alc enantioselective iridium catalyzed carbonyl allylation; oxidation level transfer hydrogenative coupling allyl acetate; departure chirally metal reagent addition crystallog; aldehyde enantioselective iridium catalyzed carbonyl allylation.

Under the conditions of transfer hydrogenation employing an iridium catalyst generated in situ from [Ir(cod)Cl]2, chiral phosphine ligand (R)-BINAP or (R)-Cl,MeO-BIPHEP, and m-nitrobenzoic acid, allyl acetate couples to allylic, aliphatic, or benzylic alcs. to furnish products of carbonyl allylation with exceptional levels of asym. induction. The very same set of optically enriched carbonyl allylation products are accessible from enals , aliphatic aldehydes , and aryl aldehydes, using iridium catalysts ligated by (-)-TMBTP or (R)-Cl,MeO-BIPHEP under identical conditions, but employing isopropanol as a hydrogen donor. A catalytically active cyclometallated complex V, which arises upon ortho-C-H insertion of iridium onto m-nitrobenzoic acid, was characterized by single-crystal x-ray diffraction. The results of isotopic labeling are consistent with intervention of sym. iridium π-allyl intermediates or rapid interconversion of σ-allyl haptomers through the agency of a sym. π-allyl. Competition experiments demonstrate rapid and reversible hydrogenation-dehydrogenation of the carbonyl partner in advance of C-C coupling. However, the coupling products, which are homoallylic alcs., experience very little erosion of optical purity by way of redox equilibration under the coupling conditions, although isopropanol, a secondary alc., may serve as terminal reductant. A plausible catalytic mechanism accounting for these observations is proposed, along with a stereochem. model that accounts for the observed sense of absolute stereoinduction. This protocol for asym. carbonyl allylation transcends the barriers imposed by oxidation level and the use of preformed allyl metal reagents.

Journal of the American Chemical Society published new progress about Alcohols, homoallylic Role: SPN (Synthetic Preparation), PREP (Preparation). 139139-86-9 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Application In Synthesis of 139139-86-9.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Guo, Yonghong; Liu, Meng-Meng; Zhu, Xujiang; Zhu, Liru; He, Chuan published the artcile< Catalytic Asymmetric Synthesis of Silicon-Stereogenic Dihydrodibenzosilines: Silicon Central-to-Axial Chirality Relay>, Formula: C44H40P2, the main research area is crystal structure mol silicon dihydrodibenzosiline heterocycle biaryl chiral preparation; rhodium catalyst asym preparation chiral silicon dihydrodibenzosiline axial; axial chirality; chirality relay; enantioselective C−H silylation; silicon-central chirality; silicon-stereogenic monohydrosilanes.

A Rh-catalyzed asym. synthesis of silicon-stereogenic dihydrodibenzosilines featuring axially chiral 6-membered bridged biaryls is demonstrated. In the presence of a RhI catalyst with a chiral diphosphine ligand, a wide range of dihydrodibenzosilines containing both silicon-central and axial chiralities are conveniently constructed in excellent enantioselectivities via dehydrogenative C(sp3)-H silylation. Absolute configuration anal. by single-crystal X-ray structures revealed a novel silicon central-to-axial chirality relay phenomenon, which we believe will inspire further research in the field of asym. catalysis and chiroptical materials.

Angewandte Chemie, International Edition published new progress about Biaryls Role: PRP (Properties), RCT (Reactant), SPN (Synthetic Preparation), RACT (Reactant or Reagent), PREP (Preparation). 139139-86-9 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Formula: C44H40P2.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Zhang, Tian-Yuan; Deng, Yi; Wei, Kun; Yang, Yu-Rong published the artcile< Enantioselective Iridium-Catalyzed Allylic Alkylation of Racemic Branched Alkyl-Substituted Allylic Acetates with Malonates>, Safety of (R)-2,2′-Bis(diphenylphosphino)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl, the main research area is alkenyl ester preparation enantioselective; alkyl substituted allylic acetate malonate allylic alkylation iridium catalyst.

The regio- and enantioselective allylic substitution of branched alkyl-substituted allylic acetates employing malonates was achieved through a process that called for Krische’s π-allyliridium C,O-benzoate catalyst. The protocol reported herein was applied to a diverse set of branched alkyl substrates that are generally not well tolerated in the other two types of Ir-catalyzed allylation.

Organic Letters published new progress about Active methylene compounds Role: RCT (Reactant), SPN (Synthetic Preparation), RACT (Reactant or Reagent), PREP (Preparation). 139139-86-9 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Safety of (R)-2,2′-Bis(diphenylphosphino)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Nishida, Goushi; Noguchi, Keiichi; Hirano, Masao; Tanaka, Ken published the artcile< Asymmetric assembly of aromatic rings to produce tetra-ortho-substituted axially chiral biaryl phosphorus compounds>, Related Products of 139139-86-9, the main research area is asym aromatic ring substituted tetra axially chiral biaryl phosphorus; dicyclohexylphosphinoyl methoxynaphthalenyl dihydroisobenzofuran preparation crystal mol structure.

Densely substituted title compounds can be obtained efficiently through an enantioselective [2 + 2 + 2] cycloaddition catalyzed by a cationic Rh1/H8-binap (H8-binap = 2,2′-bis(diphenylphosphino)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl) complex. This method is highly up to > 99% yield practical in view of the ready access to up to 98% ee substrates, mild reaction conditions, operational simplicity, and high catalytic activity. The crystal structure of one of the biaryl phosphorus compound is described.

Angewandte Chemie, International Edition published new progress about Crystal structure. 139139-86-9 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Related Products of 139139-86-9.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Masutomi, Koji; Sakiyama, Norifumi; Noguchi, Keiichi; Tanaka, Ken published the artcile< Rhodium-Catalyzed Regio-, Diastereo-, and Enantioselective [2+2+2] Cycloaddition of 1,6-Enynes with Acrylamides>, COA of Formula: C44H40P2, the main research area is enyne enantioselective diastereoselective regioselective cycloaddition acrylamide rhodium BINAP catalyst; isoindole indene isobenzofuran amide hexahydro enantioselective diastereoselective synthesis.

A variety of partially hydrogenated isoindoles I [X = NTs; R1 = H, Me, Ph; R2 = H, Me, Et, Ph; R3 = R4 = Me, n-Bu, Ph; R3 = Me, R4 = MeO, Ph; R3R4 = (CH2)4] and their carbocyclic I [X = (MeO2C)2C; R1 = R2 = R3 = Me; R4 = Ph] and oxacyclic analogs I (X = O; R1 = n-pentyl; R2 = R3 = Me; R4 = Ph) was synthesized by rhodium(I)/(R)-H8-BINAP-catalyzed asym. [2 + 2 + 2] cycloaddition of 1,6-enynes II with acrylamides H2C:CHC(O)NR3R4. In this catalysis, regioselective insertion of acrylamide into a rhodacyclopentene intermediate and the coordination of the carbonyl group of acrylamide to the cationic rhodium center suppress the undesired β-hydride elimination.

Angewandte Chemie, International Edition published new progress about Alkenynes Role: RCT (Reactant), RACT (Reactant or Reagent). 139139-86-9 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, COA of Formula: C44H40P2.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Tindall, Daniel J.; Mader, Steffen; Kindler, Alois; Rominger, Frank; Hashmi, A. Stephen K.; Schaub, Thomas published the artcile< Selective and Scalable Synthesis of Sugar Alcohols by Homogeneous Asymmetric Hydrogenation of Unprotected Ketoses>, Synthetic Route of 139139-86-9, the main research area is stereoselective hydrogenation catalyst catalysis alditol monosaccharide ketose; asymmetric catalysis; hydrogenation; industrial chemistry; ruthenium; sugar alcohol.

Sugar alcs. are of great importance for the food industry and are promising building blocks for bio-based polymers. Industrially, they are produced by heterogeneous hydrogenation of sugars with H2, usually with none to low stereoselectivities. Now, we present a homogeneous system based on com. available components, which not only increases the overall yield, but also allows a wide range of unprotected ketoses to be diastereoselectively hydrogenated. Furthermore, the system is reliable on a multi-gram scale allowing sugar alcs. to be isolated in large quantities at high atom economy.

Angewandte Chemie, International Edition published new progress about Alditols Role: SPN (Synthetic Preparation), PREP (Preparation). 139139-86-9 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Synthetic Route of 139139-86-9.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Zhang, Xiaoyong; Mashima, Kazushi; Koyano, Kinko; Sayo, Noboru; Kumobayashi, Hidenori; Akutagawa, Susumu; Takaya, Hidemasa published the artcile< Synthesis of partially hydrogenated 2,2'-bis(diphenylphosphenyl)-1,1'-binaphthyl (BINAP) ligands and their application to catalytic asymmetric hydrogenation>, Safety of (R)-2,2′-Bis(diphenylphosphino)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl, the main research area is bisphosphine chiral partially hydrogenated synthesis ligand; ruthenium catalyst hydrogenation chiral phosphine ligand; asym hydrogenation ruthenium catalyst chiral phosphine; crystal structure chiral diphosphine ruthenium cation; mol structure chiral diphosphine ruthenium cation.

Three pairs of new axially dissym. bisphosphine ligands, (R)-(-)- and (S)-(+)-2,2′-bis(dicyclohexylphosphinyl)-1,1′-binaphthyl [ I, R = C6H11], (R)-(+)- and (S)-(-)-2,2′-bis(diphenylphosphinyl)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl [II, R = Ph], and (R)-(-)- and (S)-(+)-2,2′-bis(dicyclohexylphosphinyl)-5,5′,6,6,7,7′,8,8′-octahydro-1,1′-binaphthyl [II, R = C6H11], have been synthesized. The absolute configurations of the isomers I were determined by single-crystal x-ray diffraction of the linear 1:1 polymeric complex of (S)-(+)-2,2′-bis(dicyclohexylphosphinoyl)-1,1′-binaphthyl [III] and (2R,3R)-(-)-di-O-benzoyltartaric acid [(-)-DBT], and those of the isomers II were established on the basis of CD spectra of the phosphanes and their bisoxides. X-ray crystallog. studies of two cationic Rh1 complexes, [Rh{(S)-Cy-binap}(COD)]ClO4 [(S)-IV] and [Rh{(S)-H8-binap}(COD)]ClO4[(S)-V], revealed that complex (S)-IV possesses a disym. structure, while complex (S)-V has a pseudo-C2-symmetry and shows a significantly large dihedral angle between the two Ph rings [80.3(4)°]. The potentially of ligand II for asym. catalysis was demonstrated in RuII-catalyzed stereoselective hydrogenations of Me 2-(benzamidomethyl)-3-oxobutanoate, (in up to 92% d.e. and 99% e.e.) and geraniol (in 98% optical purity).

Journal of the Chemical Society, Perkin Transactions 1: Organic and Bio-Organic Chemistry (1972-1999) published new progress about Crystal structure. 139139-86-9 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Safety of (R)-2,2′-Bis(diphenylphosphino)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate