Day: October 11, 2022

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

Nishida, Goushi; Noguchi, Keiichi; Hirano, Masao; Tanaka, Ken published the artcile< Enantioselective synthesis of P-stereogenic alkynylphosphine oxides by Rh-catalyzed [2+2+2] cycloaddition>, Category: chiral-phosphine-ligands, the main research area is alkynyl phosphine oxide preparation stereoselective structure; cycloaddition dialkynyl phosphine oxide diyne rhodium binap complex catalyst; crystal mol structure stereogenic phosphorus alkynyl phosphine oxide preparation.

An enantioselective synthesis of P-stereogenic alkynylphosphine oxides through a cationic rhodium(l)/modified-binap complex catalyzed [2+2+2] cycloaddition of sym. dialkynylphosphine oxides with 1,6-diynes was developed (binap = 2,2′-bis(diphenylphosphinyl)-1,1′-binaphthyl, Z = CH2, O, or N-sulfonamide). Furthermore, this method permits the synthesis of a C2-sym. P-stereogenic bis(alkynylphosphine oxide). A crystal structure of one product was determined along with the absolute configuration of the phosphorus center.

Angewandte Chemie, International Edition published new progress about Alkadiynes Role: RCT (Reactant), RACT (Reactant or Reagent) (1,6-diynes). 139139-86-9 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, 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

Fernandez, Marti; Parera, Magda; Parella, Teodor; Lledo, Agusti; Le Bras, Jean; Muzart, Jacques; Pla-Quintana, Anna; Roglans, Anna published the artcile< Rhodium-Catalyzed [2+2+2] Cycloadditions of Diynes with Morita-Baylis-Hillman Adducts: A Stereoselective Entry to Densely Functionalized Cyclohexadiene Scaffolds>, COA of Formula: C44H40P2, the main research area is cyclohexadiene scaffold enantioselective preparation; diyne Morita Baylis Hillman adduct enantioselective cycloaddition rhodium catalyst.

A rhodium-catalyzed asym. synthesis of 5,5-disubstituted cyclohexa-1,3-dienes has been achieved by [2+2+2] cycloaddition reactions between diynes and Morita-Baylis-Hillman (M-B-H) adducts as unsaturated substrates. Products containing two adjacent chiral centers (quaternary and tertiary, resp.) were obtained with complete diastereoselectivity and high enantioselectivity (84-97%) through a kinetic resolution of the M-B-H adduct. Furthermore, these highly substituted cyclohexadienes reacted with dienophiles to afford the corresponding Diels-Alder cycloadducts in good yields.

Advanced Synthesis & Catalysis published new progress about Alkadiynes 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, 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

Trost, Barry M.; Thaisrivongs, David A. published the artcile< Strategy for Employing Unstabilized Nucleophiles in Palladium-Catalyzed Asymmetric Allylic Alkylations>, Recommanded Product: N,N’-(11R,12R)-(9,10-Dihydro-9,10-ethanoanthracene-11,12-diyl)bis[2-(diphenylphosphino)benzamide], the main research area is strategy employing unstabilized nucleophile palladium catalyzed asym allylic alkylation.

The authors report a strategy for the employment of highly unstabilized anions in palladium-catalyzed asym. allylic alkylations (AAA). The hard 2-methylpyridyl nucleophiles studied are first reacted in situ with BF3•OEt2; subsequent deprotonation of the resulting complexes with LiHMDS affords soft anions that are competent nucleophiles in AAA reactions. The reaction is selective for the 2-position of methylpyridines and tolerates bulky aryl and alkyl substitution at the 3-, 4-, and 5-positions. Studies into the reaction mechanism demonstrate that the configuration of the allylic stereocenter is retained, consistent with the canonical outer sphere mechanism invoked for palladium-catalyzed allylic substitution processes of stabilized anions.

Journal of the American Chemical Society published new progress about Allylic alkylation catalysts, stereoselective. 152140-65-3 belongs to class chiral-phosphine-ligands, and the molecular formula is C54H42N2O2P2, Recommanded Product: 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

Bates, Roderick W.; Li, Lu; Palani, Kalpana; Phetsang, Wanida; Loh, Joanna Kejun published the artcile< Synthesis of the Tetrahydropyran Fragment of Bistramide D>, Application In Synthesis of 152140-65-3, the main research area is bistramide D tetrahydropyran fragment enantioselective preparation.

A synthesis of the tetrahydropyran (THP) moiety of bistramide D has been completed by using cross-metathesis and kinetically controlled intramol. oxa-Michael addition to form the ring with excellent trans selectivity. The C9 Me substituent was introduced by using an unsaturated sulfone building block, which can be most effectively prepared through a combination of diastereoselective allylation and alkene isomerisation. The effect of this Me group on subsequent cross-metathesis reactions can be mitigated by careful choice of reaction conditions.

Asian Journal of Organic Chemistry published new progress about Cross-metathesis. 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