Month: October 2022

Cobley, Christopher J.; Lennon, Ian C.; Praquin, Celine; Zanotti-Gerosa, Antonio; Appell, Robert B.; Goralski, Christian T.; Sutterer, Angela C. published the artcile< Highly Efficient Asymmetric Hydrogenation of 2-Methylenesuccinamic Acid Using a Rh-DuPHOS Catalyst>, Category: chiral-phosphine-ligands, the main research area is methylsuccinamic acid enantioselective preparation; methylenesuccinamic acid preparation; asym hydrogenation methylenesuccinamic acid rhodium DuPHOS catalyst; chloride residue methylenesuccinamic acid hindrance asym hydrogenation.

Nonracemic 2-methylsuccinamic acid HO2CCHMeCH2CONH2 is prepared efficiently in two steps from itaconic anhydride using an asym. hydrogenation as the key step. Ring opening of itaconic anhydride with an aqueous solution of ammonium hydroxide followed by neutralization with sulfuric acid yields 2-methylenesuccinamic acid HO2CC(:CH2)CH2CONH2 in 53% yield after recrystallization to remove 3-methylenesuccinamic acid present as an impurity. The use of hydrochloric acid in the neutralization step as in previous procedures leads to the presence of chloride residues in the product; hydrogenation of 2-methylenesuccinamic acid containing chloride residues requires higher loadings of catalyst and longer reaction times, although the enantiomeric excess of the 2-methylsuccinamic acid produced is unaffected. Using 0.001 mol% {[(S,S)-Et-DuPHOS]Rh(COD)}+BF4- as the precatalyst for hydrogenation of 2-methylenesuccinamic acid in methanol under 140 atm of hydrogen at 45°, (R)-2-methylsuccinamic acid is obtained in 96% ee. Single-crystal digestion of (R)-2-methylsuccinamic acid obtained from the hydrogenation yields (R)-2-methylsuccinamic acid in >99.5% ee and 77% conversion containing less than 1 ppm rhodium.

Organic Process Research & Development published new progress about Hydrogenation catalysts, stereoselective. 325168-88-5 belongs to class chiral-phosphine-ligands, and the molecular formula is C48H50P2, Category: chiral-phosphine-ligands.

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

Trost, Barry M.; Frederiksen, Mathias U. published the artcile< Palladium-catalyzed asymmetric allylation of prochiral nucleophiles: synthesis of 3-allyl-3-aryl oxindoles>, Application In Synthesis of 152140-65-3, the main research area is arylindolinone allyl acetate allylation palladium chiral phosphine; allyl arylindolinone asym preparation; palladium chiral phosphine asym allylation catalyst.

Excellent yields and enantioselectivies were attained in the synthesis of 3-alkyl-3-aryloxindoles, e.g., I, based on the Pd-catalyzed asym. allylic alkylation reaction. This approach utilizes a nonbasic hydroxylic additive in the transformation of 3-aryloxindoles into complex, synthetically valuable oxindoles.

Angewandte Chemie, International Edition published new progress about Allylation catalysts. 152140-65-3 belongs to class chiral-phosphine-ligands, and the molecular formula is C54H42N2O2P2, Application In Synthesis of 152140-65-3.

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

Grasa, Gabriela A.; Zanotti-Gerosa, Antonio; Ghosh, Shyamali; Teleha, Christopher A.; Kinney, William A.; Maryanoff, Bruce E. published the artcile< Efficient, enantioselective synthesis of a β,β-disubstituted carboxylic acid by Ru-XylPhanePhos-catalyzed asymmetric hydrogenation>, Reference of 325168-88-5, the main research area is piperidinebutenoic acid quinolinyl stereoselective reduction phanephos ruthenium catalyst.

Enantioselective preparation of a key αvβ3 integrin antagonist intermediate, (3S)-3-(quinolin-3-yl)-4-(1-tert.-butoxycarbonylpiperidin-4-yl)butanoic acid, was accomplished via catalytic asym. hydrogenation of the corresponding but-2-enoic acid. The successful application of a Ru-(R)-XylPhanePhos catalyst to this type of substrate is unprecedented. In situ NMR experiments of pre-catalyst formation/activation by CH3CO2H, and reaction parameter modification, revealed that [Ru(COD)(CF3CO2)2]2/(R)-XylPhanePhos is a highly active and efficient catalytic system.

Tetrahedron Letters published new progress about Hydrogenation catalysts, stereoselective. 325168-88-5 belongs to class chiral-phosphine-ligands, and the molecular formula is C48H50P2, Reference of 325168-88-5.

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>, Recommanded Product: (S)-(-)-2,2′-Bis(diphenylphosphino)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl, 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. 139139-93-8 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Recommanded Product: (S)-(-)-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

Larksarp, Chitchamai; Sellier, Odile; Alper, Howard published the artcile< Palladium-Catalyzed Cyclization Reactions of 2-Vinylthiiranes with Heterocumulenes. Regioselective and Enantioselective Formation of Thiazolidine, Oxathiolane, and Dithiolane Derivatives>, COA of Formula: C32H40FeP2, the main research area is thiazolidineimine enantioselective regioselective preparation; thiazolidine oxathiolane dithiolane regioselective preparation; palladium catalyst ring expansion reaction vinylthiirane carbodiimide isocyanate; isothiocyanate keteneimine ketene ring expansion reaction vinylthiirane palladium catalyst; diphosphine ligand enantioselective ring expansion reaction vinylthiirane carbodiimide; heterocumulene ring expansion reaction vinylthiirane palladium catalyst.

Sulfur-containing five-membered-ring heterocycles such as I (R = H, Me; R1 = 4-ClC6H4, 4-BrC6H4, 2-ClC6H4, 4-O2NC6H4, 4-MeC6H4, Ph; X = R1N, O; Y = R1N, S) are prepared by palladium-catalyzed ring expansion reactions of 2-vinylthiirane and 2-methyl-2-vinylthiirane with carbodiimides, isocyanates, isothiocyanates, and ketenimines in the presence of bidentate phosphine ligands such as BINAP or 1,3-bis(diphenylphosphino)propane (dppp). E.g., 2.5 mol% of the chloroform adduct of tris(dibenzylideneacetone)dipalladium and 5 mol% of dppp were stirred in THF under nitrogen pressure for 30 min.; 2 equivalent of 2-vinylthiirane and 1 equivalent of di(4-chlorophenyl)carbodimide were added and the mixture stirred for 24h at 50° to give thiazolidineimine I (R = H; R1 = 4-ClC6H4; X = Y = R1N) in 97% yield. Using nonracemic ligands such as (S)-tol-BINAP and (R)-BINAP in the palladium-catalyzed ring expansion reaction gave the enantiomers of I (R = H; R1 = 4-ClC6H4; X = Y = R1N) in 63 and 68% ee, resp.

Journal of Organic Chemistry published new progress about Carbodiimides Role: RCT (Reactant), RACT (Reactant or Reagent). 277306-29-3 belongs to class chiral-phosphine-ligands, and the molecular formula is C32H40FeP2, COA of Formula: 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

Seraphim, Thiago V.; Nano, Nardin; Cheung, Yiu Wing Sunny; Aluksanasuwan, Siripat; Colleti, Carolina; Mao, Yu-Qian; Bhandari, Vaibhav; Young, Gavin; Holl, Larissa; Phanse, Sadhna; Gordiyenko, Yuliya; Southworth, Daniel R.; Robinson, Carol V.; Thongboonkerd, Visith; Gava, Lisandra M.; Borges, Julio C.; Babu, Mohan; Barbosa, Leandro R. S.; Ramos, Carlos H. I.; Kukura, Philipp; Houry, Walid A. published the artcile< Assembly principles of the human R2TP chaperone complex reveal the presence of R2T and R2P complexes>, SDS of cas: 606-68-8, the main research area is chaperone complex Armadillo repeat domain folded protein; AAA+ proteins; ATPases; PAQosome; R2TP; RUVBL1/2; macromolecular complex assembly; molecular chaperones; protein folding.

R2TP is a highly conserved chaperone complex formed by two AAA+ ATPases, RUVBL1 and RUVBL2, that associate with PIH1D1 and RPAP3 proteins. R2TP acts in promoting macromol. complex formation. Here, we establish the principles of R2TP assembly. Three distinct RUVBL1/2-based complexes are identified: R2TP, RUVBL1/2-RPAP3 (R2T), and RUVBL1/2-PIH1D1 (R2P). Interestingly, we find that PIH1D1 does not bind to RUVBL1/RUVBL2 in R2TP and does not function as a nucleotide exchange factor; instead, RPAP3 is found to be the central subunit coordinating R2TP architecture and linking PIH1D1 and RUVBL1/2. We also report that RPAP3 contains an intrinsically disordered N-terminal domain mediating interactions with substrates whose sequences are primarily enriched for Armadillo repeat domains and other helical-type domains. Our work provides a clear and consistent model of R2TP complex structure and gives important insights into how a chaperone machine concerned with assembly of folded proteins into multisubunit complexes might work.

Structure (Oxford, United Kingdom) published new progress about A-kinase anchor protein 4 Role: BSU (Biological Study, Unclassified), BIOL (Biological Study). 606-68-8 belongs to class chiral-phosphine-ligands, and the molecular formula is C21H27N7Na2O14P2, SDS of cas: 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

Tang, Liang L.; Ryabov, Alexander D.; Collins, Terrence J. published the artcile< Kinetic Evidence for Reactive Dimeric TAML Iron Species in the Catalytic Oxidation of NADH and a Dye by O2 in AOT Reverse Micelles>, Related Products of 606-68-8, the main research area is kinetics reactive dimeric TAML iron species; catalytic oxidation NADH dye oxygen AOT reverse micelle.

The efficacy of the iron(III) TAML activator [Fe{C6H4-1,2-(N1COCMe2N2CO)2CMe2(Fe-N1)(Fe-N2)}(OH2)]- (1) for the catalytic activation of dioxygen in reverse micelles of Aerosol OT (AOT) in n-octane has been studied. Kinetic evidence is presented for the existence of unusual second-order catalytic pathways in the oxidation of NADH to NAD+ and the bleaching of blue pinacyanol chloride (PNC) dye. Depending on the substrate and reaction conditions, a second-order pathway in [1] either dominates or proceeds in obvious combination with a first-order pathway in [1]. Detailed kinetic anal. of the exptl. data supports the previously made hypothesis that the reactive intermediate is associated with the mixed-valent dimer system [LFeIIIOFeIVL]3-/[LFeIII(OH)FeIVL]2-.

ACS Catalysis published new progress about Bleaching. 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

Oonishi, Yoshihiro; Saito, Akira; Sato, Yoshihiro published the artcile< Rhodium(I)-Catalyzed Intermolecular [2+2+2] Cycloaddition of Allenyl Aldehydes with Alkynes and Related Cyclization>, Product Details of C44H40P2, the main research area is polysubstituted dihydropyran enantioselective preparation; internal alkyne allenyl aldehyde rhodium catalyst regioselective cycloaddition; dienyl ketone preparation; terminal alkyne allenyl aldehyde rhodium catalyst cycloaddition.

Rhodium(I)-catalyzed cyclization of allenyl aldehydes with various alkynes was investigated. The intermol. [2+2+2] cycloaddition reaction of allenyl aldehyde with internal alkynes that have both an electron-rich aromatic ring and an electron-withdrawing group at the terminus afforded polysubstituted dihydropyran for e.g., I in good yields with good to high regio- and enantioselectivity. While the reactions of terminal alkynes with allenyl aldehyde gave dienyl ketones instead of [2+2+2] cycloaddition products for e.g., II in good yields.

Asian Journal of Organic Chemistry published new progress about Alkadienones 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, Product Details 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

Park, Jihye; Kim, Young Kwang; Kim, Guncheol published the artcile< Stereoselective formal synthesis of (-)-mesembrane via asymmetric allylation and resoluting condensation reactions>, Safety of N,N’-(11R,12R)-(9,10-Dihydro-9,10-ethanoanthracene-11,12-diyl)bis[2-(diphenylphosphino)benzamide], the main research area is phenylcyclohexanone asym asym allylation; oxocyclohexaneacetamide intramol cyclocondensation resolution; mesembrane stereoselective formal synthesis.

A selective pathway to (-)-mesembrane by a combination of enantioselective allylation and intramol. amide-ketone cyclization was developed.

Bulletin of the Korean Chemical Society published new progress about Allylation, stereoselective. 152140-65-3 belongs to class chiral-phosphine-ligands, and the molecular formula is C54H42N2O2P2, Safety of N,N’-(11R,12R)-(9,10-Dihydro-9,10-ethanoanthracene-11,12-diyl)bis[2-(diphenylphosphino)benzamide].

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

Desfeux, Camille; Besnard, Celine; Mazet, Clement published the artcile< [n]Dendralenes as a Platform for Selective Catalysis: Ligand-Controlled Cu-Catalyzed Chemo-, Regio-, and Enantioselective Borylations>, Name: (R)-2,2′-Bis(diphenylphosphino)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl, the main research area is phosphanamine copper catalyzed antiMarkovnikov enantioselective borylation substituted dendralene; dendralene preparation enantioselective borylation; crystal structure benzoyl dendralene derivative; mol structure benzoyl dendralene derivative.

The authors report the development of two complementary methods for the Cu-catalyzed anti-Markovnikov borylation of one specific olefin in 2-substituted [n]dendralenes (n = 3-6). The 1st protocol operates with a bisphosphine ligand and occurs with high regio- and chemoselectivity for the terminal double bond, independently of the number of cross-conjugated alkenes. The use of a chiral phosphanamine ligand enables the highly chemo-, regio-, and enantioselective borylation of the alkene cross-conjugated with the terminal olefin in [n]dendralenes.

Organic Letters published new progress about Borylation (anti-Markovnikov enantioselective). 139139-86-9 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Name: (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