Month: October 2022

Oonishi, Yoshihiro; Masusaki, Shuichi; Sakamoto, Shunki; Sato, Yoshihiro published the artcile< Rhodium(I)-Catalyzed Enantioselective Cyclization of Enynes by Intramolecular Cleavage of the Rh-C Bond by a Tethered Hydroxy Group>, Safety of (R)-2,2′-Bis(diphenylphosphino)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl, the main research area is acyl heterocyclic compound enantioselective preparation; enynol preparation enantioselective cyclization rhodium catalyst; cyclization; enantioselectivity; enyne; rhodium; σ-bond metathesis.

Rhodium(I)-catalyzed enantioselective intramol. cyclization of enynes having a hydroxy group in the tether was investigated, and various cyclic compounds possessing a chiral quaternary carbon center were obtained in high yields with high ees. In this cyclization, a Rh-C(sp2) bond in the rhodacyclopentene intermediate, which was formed by enantioselective oxidative cycloaddition of enynes to a chiral rhodium(I) complex, was intramolecularly cleaved by σ-bond metathesis of a tethered O-H bond in the substrate. Furthermore, it was found that the cyclic compounds were obtained with high ees even when the starting materials having a racemic secondary alc. moiety were used in this reaction.

Angewandte Chemie, International Edition published new progress about Alcohols, unsaturated 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

Oonishi, Yoshihiro; Hato, Yoshio; Sato, Yoshihiro published the artcile< Rhodium(I)-Catalyzed Diastereoselective Cycloisomerization of Enynes with Tethered (S)-2-Methyl-2-propanesulfinyl Imine>, Application of C44H40P2, the main research area is enyne tethered sulfinyl imine rhodium catalyst cycloisomerization; cyclic diene enantioselective diastereoselective preparation dienophile Diels Alder reaction; spiroamide diastereoselective enantioselective preparation.

The rhodium(I)-catalyzed cycloisomerization of enynes with tethered (S)-2-methyl-2-propanesulfinyl imine afforded 5- or 6-membered cyclic compounds containing exocyclic 1,3-diene moieties in a stereoselective manner. The reaction proceeded through β-hydride elimination of a 7-membered azarhodacycle intermediate, which was generated from three unsaturated bonds (i.e., alkene, alkyne, and C-N bonds) and an Rh(I) complex. The resultant cyclic compounds could be reacted with various dienophiles to afford spiroamides as single isomers through the Diels-Alder reaction.

Advanced Synthesis & Catalysis published new progress about Alkenynes Role: RCT (Reactant), SPN (Synthetic Preparation), RACT (Reactant or Reagent), PREP (Preparation). 139139-93-8 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Application of 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

Kashima, Kenichi; Ishii, Masahiro; Tanaka, Ken published the artcile< Synthesis of Pyridylphosphonates by Rhodium-Catalyzed [2+2+2] Cycloaddition of 1,6- and 1,7-Diynes with Diethyl Phosphorocyanidate>, Quality Control of 139139-86-9, the main research area is diyne cycloaddition enantioselective phosphorocyanidate preparation pyridylphosphonate fluorescence.

The convenient and atom-economical synthesis of substituted bicyclic pyridylphosphonates was achieved by the cationic Rh(I)/H8-binap-complex-catalyzed [2+2+2] cycloaddition of 1,6- and 1,7-diynes with di-Et phosphorocyanidate. These reactions may proceed via an azarhodacyclopentadiene intermediate in addition to the rhodacyclopentadiene intermediate.

European Journal of Organic Chemistry published new progress about Alkadiynes Role: RCT (Reactant), RACT (Reactant or Reagent). 139139-86-9 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Quality Control 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

Yu, Chang-Bin; Wang, Jie; Zhou, Yong-Gui published the artcile< Facile synthesis of chiral indolines through asymmetric hydrogenation of in situ generated indoles>, Recommanded Product: (R)-2,2′-Bis(diphenylphosphino)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl, the main research area is indoline enantioselective preparation; butoxycarbonyloxoalkylaniline cascade condensation hydrogenation.

A concise and enantioselective procedure for the synthesis of optically active indolines I [R = Me, n-Bu, Bn, etc.; R1 = H, 2-Me, 2-OMe, 4-OMe, 2,4-di-Me] was developed through intramol. condensation, deprotection and palladium-catalyzed asym. hydrogenation in a one-pot process with up to 96% ee. A strong Bronsted acid played an important role in both the formation of indoles and asym. hydrogenation process. This strategy could be scaled-up with excellent reactivity and enantioselectivity.

Organic Chemistry Frontiers published new progress about Anilines Role: RCT (Reactant), RACT (Reactant or Reagent). 139139-86-9 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Recommanded Product: (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

Lautens, M.; Fagnou, K. published the artcile< Rhodium-catalyzed asymmetric ring opening reactions with carboxylate nucleophiles>, Product Details of C32H40FeP2, the main research area is stereoselective ring opening oxabenzonorbornadiene carboxylate; rhodium stereoselective ring opening oxabenzonorbornadiene carboxylate; epoxynaphthalene stereoselective ring opening carboxylate.

An asym. ring opening reaction of oxabenzonorbornadiene with carboxylate nucleophiles to generate enantiomerically enriched naphthalene-derived products containing an allylic carboxylate moiety was developed. These reactions occur in good yield and excellent enantioselectivity (>90% ee). The allylic carboxylate functionality was found to be stable towards reaction with the rhodium catalyst under the reaction conditions. In order to obtain these results, two advancements were required. First, the use of protic additives was necessary for good reactivity. Second, the exchange of the halide ligand on the catalyst from chloride to iodide was required to obtain high ee.

Tetrahedron published new progress about Nucleophiles. 277306-29-3 belongs to class chiral-phosphine-ligands, and the molecular formula is C32H40FeP2, Product Details of C32H40FeP2.

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

Ludwig, Janet C.; Misiorowski, Ronald L.; Chvapil, Milos; Seymour, Michael D. published the artcile< Interaction of zinc ions with electron carrying coenzymes NADPH and NADH>, Related Products of 606-68-8, the main research area is zinc NADH drug metabolism inhibition.

The substrate for the drug-oxidizing system, NADPH, binds to Zn2+, but NADH does not. Equilibrium gel filtration and acid titrations of Zn2+ and NADPH tetrasodium salt indicated a molar ratio of metal to nucleotide of 2:1 and a formation constant of 106.75. 31P-NMR, UV, and fluorescence spectra of the complex indicated the possible binding sites of Zn2+ to NADPH. Since Zn2+ is known to inhibit the metabolism of drugs by mixed function oxidases in liver microsomes, the formation of the Zn2+-NADPH complex suggests the mechanism by which Zn2+ may inhibit the drug-oxidizing system.

Chemico-Biological Interactions published new progress about Drug-metabolizing enzymes Role: BIOL (Biological Study). 606-68-8 belongs to class chiral-phosphine-ligands, and the molecular formula is C21H27N7Na2O14P2, Related Products of 606-68-8.

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

Tominaga, Masato; Iwaoka, Ayako; Kawai, Daisuke; Sakamoto, Shingo published the artcile< Correlation between carbon oxygenated species of SWCNTs and the electrochemical oxidation reaction of NADH>, Product Details of C21H27N7Na2O14P2, the main research area is oxygenated carbon nanotube correlation electrochem oxidation NADH.

The correlation between carbon oxygenated species as a defect in single-walled carbon nanotubes (SWCNTs) and the oxidation reaction behavior of the reduced form of β-nicotinamide dinucleotide (NADH) was investigated. The two main oxidation peaks of NADH at the SWCNTs were due to adsorbed and diffused species, resp. The peak current ratio showed a good relationship to the intensity ratio of the G-band/D-band obtained from the Raman spectra of the SWCNTs.

Electrochemistry Communications published new progress about Carbon nanotubes (oxygenated). 606-68-8 belongs to class chiral-phosphine-ligands, and the molecular formula is C21H27N7Na2O14P2, Product Details of C21H27N7Na2O14P2.

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

Shibuya, Tetsuro; Nakamura, Kyosuke; Tanaka, Ken published the artcile< Cationic gold(I) axially chiral biaryl bis[phosphine] complex-catalyzed atroposelective synthesis of heterobiaryls>, Related Products of 139139-86-9, the main research area is heterobiaryl atropisomer preparation; naphthopyran benzoquinoline naphthalenyl biaryl atropisomer preparation; asymmetric catalysis; axial chirality; gold; heterobiaryls; hydroarylation.

It has been established that a cationic gold(I)/(R)-DTBM-Segphos or (R)-BINAP complex catalyzes an atroposelective intramol. hydroarylation of alkynes leading to enantioenriched axially chiral 4-aryl-2-quinolinones and 4-(aryl)coumarins and the synthesis of the target compounds was achieved with up to 61% ee.

Beilstein Journal of Organic Chemistry published new progress about Atropisomers. 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

Shen, Zengming; Lu, Xiyan; Lei, Aiwen published the artcile< Highly enantioselective hydrogenation of exocyclic double bond of N-tosyloxazolidinones catalyzed by a neutral rhodium complex and its synthetic applications>, Related Products of 139139-93-8, the main research area is alkylideneoxazolidinone stereoselective hydrogenation rhodium catalyst.

A highly enantioselective synthesis of optically active N-tosyl-4-alkyl-1,3-oxazolidin-2-ones based on the asym. hydrogenation of the trisubstituted exocyclic double bond of N-tosyl-4-alkylidene-1,3-oxazolidin-2-ones under the catalysis of neutral [Rh(COD)Cl]2 and (S)-(+)-DTBM-SEGPHOS was developed. The utility of this highly enantioselective reaction was exemplified by the synthesis of optically active amino acids, amino alcs., and piperidine derivatives

Tetrahedron published new progress about Amino acids Role: SPN (Synthetic Preparation), PREP (Preparation). 139139-93-8 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Related Products of 139139-93-8.

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

Nogami, Juntaro; Tanaka, Yusuke; Sugiyama, Haruki; Uekusa, Hidehiro; Muranaka, Atsuya; Uchiyama, Masanobu; Tanaka, Ken published the artcile< Enantioselective Synthesis of Planar Chiral Zigzag-Type Cyclophenylene Belts by Rhodium-Catalyzed Alkyne Cyclotrimerization>, Quality Control of 139139-93-8, the main research area is zigzag cyclophenylene belt enantioselective preparation; rhodium catalyst enantioselective cyclotrimerization heptynyl oxypropynylphenoxyphenylene oligomer; mol crystal structure racemic zigzag cyclophenylene belt; mechanism enantioselectivity cyclotrimerization heptynyl oxypropynylphenoxyphenylene; ring strain calculated zigzag cyclophenylene belt; fluorescence UV visible absorption zigzag cyclophenylene belt; dissymetry factor ECD CPL nonracemic zigzag cyclophenylene belt.

Planar chiral zigzag-type [8] and [12]cyclophenylene belts were prepared enantioselectively by rhodium-catalyzed enantioselective intramol. sequential cyclotrimerizations of a cyclic [oxypropynylbis(heptynyloxy)phenoxybis(heptynyl)phenylene] dimer and trimer. The observed enantioselectivity likely arose from the regioselective formation of a rhodacyclic intermediate from an unsym. triyne unit. The structure of the racemic zigzag [8]cyclophenylene belt was determined by X-ray crystallog.; the homochiral belts mesh with one another to form columns in the solid state, with columns of alternating chiralities. The ring strain of the zigzag [8]cyclophenylene belt was smaller than that of the corresponding armchair-type cycloparaphenylene despite its smaller ring size because of the presence of strain-relieving m-terphenyl moieties. The effect of the number of the benzene rings in the zigzag cyclophenylene belts on their UV/visible absorption and fluorescence was small because of the interruption of conjugation by the m-phenylene moieties, but the effect of bending on the absorption and emission peaks and on the absolute fluorescence quantum yield was significant. Modest anisotropy dissymmetry factors of the electronic CD and CPL spectra were observed for the zigzag [8]cyclophenylene belt.

Journal of the American Chemical Society published new progress about Circular dichroism (electronic). 139139-93-8 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Quality Control of 139139-93-8.

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