Month: October 2022

Yoshida, Mariko; Nemoto, Tetsuhiro; Zhao, Zengduo; Ishige, Yuta; Hamada, Yasumasa published the artcile< Enantioselective construction of all-carbon quaternary spirocenters through a Pd-catalyzed asymmetric intramolecular ipso-Friedel-Crafts allylic alkylation of phenols>, Computed Properties of 325168-88-5, the main research area is spirocyclohexadienone enantioselective synthesis; phenol Friedel Crafts allylic alkylation chiral ligand Pd catalyst.

A novel catalytic asym. synthetic method for making spirocyclohexadienones e. g., I with an all-carbon quaternary spirocenter was developed based on the Pd-catalyzed intramol. ipso-Friedel-Crafts allylic alkylation of phenols. When 5 mol % of the Pd catalyst and 12 mol % of (-)-9-NapBN (-) were used, the spirocyclic adduct was obtained with up to 93% ee, albeit with low chem. yield. On the other hand, when using 6 mol% of the Trost ligand (R,R), the spirocyclic adducts were obtained in good yields with up to 89% ee (diastereoselectivity = 9.2:1).

Tetrahedron: Asymmetry published new progress about Allylic alkylation. 325168-88-5 belongs to class chiral-phosphine-ligands, and the molecular formula is C48H50P2, Computed Properties 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

Shibata, Takanori; Arai, Yoshikazu; Tahara, Yuki published the artcile< Enantioselective Construction of Quaternary Carbon Centers by Catalytic [2 + 2 + 2] Cycloaddition of 1,6-Enynes and Alkynes>, COA of Formula: C44H40P2, the main research area is bicyclic cyclohexadiene quaternary carbon stereocenter preparation; enyne alkyne enantioselective cycloaddition chiral rhodium catalysis.

The enantioselective [2 + 2 + 2] cycloaddition of 1,6-enynes and alkynes using chiral rhodium catalysts gave cycloadducts containing quaternary carbon stereocenters. Both sym. and unsym. alkynes and acetylene could be used as coupling partners, and the corresponding bicyclic cyclohexa-1,3-dienes were obtained in good to excellent ee.

Organic Letters published new progress about Alkenynes Role: RCT (Reactant), RACT (Reactant or Reagent). 139139-93-8 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

Tian, Sicong; Lei, Peng; Zhang, Jing; Sun, Yao; Li, Baolong; Shan, Yujuan published the artcile< Sulforaphane Balances Ca2+ Homeostasis Injured by Excessive Fat via Mitochondria-Associated Membrane (MAM)>, Product Details of C21H27N7Na2O14P2, the main research area is sulforaphane homeostasis fat mitochondria associated membrane; Ca2+ homeostasis; lipid metabolism; mitochondria function; mitochondria-associated membrane; sulforaphane.

Mitochondria-associated membrane (MAM) connects endoplasmic reticulum (ER) and mitochondria plays a significant role in lipid metabolism and Ca2+ homeostasis. Albeit sulforaphane (SFN) shows potential in ameliorating excessive fat accumulation and mitochondrial function; whether MAM is a target of SFN and its underlying mechanisms are still unclear. High-fat-intake models are established both in vivo and in vitro. SFN widens the distance between ER and mitochondria and down-regulates MAM tether protein mitofusin-2. SFN reverses the increase of Ca2+ induced by fatty acid and inhibits the Ca2+ channel inositol-1,4,5-trisphosphate receptor (IP3R). Compared with high fat group, SFN alleviates Ca2+ overload in the mitochondria and suppresses mitochondrial calcium uniporter (MCU). Furthermore, SFN increases mitochondrial DNA quantities and mitochondria membrane potential, while decreasing reactive oxygen species (ROS) production Finally, SFN increases mitochondria complexes IV content and ATP synthesis. These results suggest that SFN balances the Ca2+ homeostasis in the MAM through regulating Ca2+ flux by Ca2+ channel IP3R and MCU.

Molecular Nutrition & Food Research published new progress about Endoplasmic reticulum. 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

Miyauchi, Yuta; Noguchi, Keiichi; Tanaka, Ken published the artcile< Rhodium-Catalyzed One-Pot Intermolecular [2 + 2 + 2] Trimerization/Asymmetric Intramolecular [4 + 2] Cycloaddition of Two Aryl Ethynyl Ethers and 5-Alkynals>, Application In Synthesis of 139139-86-9, the main research area is rhodium catalyst trimerization asym cycloaddition aryl ethynyl ether alkynal; cyclohexadiene annulated enantioselective regioselective synthesis.

It has been established that a cationic Rh(I)/(R)-H8-BINAP complex catalyzes the one-pot intermol. [2+2+2] trimerization/asym. intramol. [4+2] cycloaddition of two aryl ethynyl ethers and 5-alkynals to produce annulated 1,4-cyclohexadienes possessing two stereogenic centers. E.g., rhodium-catalyzed reaction of 2-(ethynyloxy)naphthalene and MeCCCH2NTsCH2CHO gave 64% annulated 1,4-cyclohexadiene derivative (I).

Organic Letters published new progress about [4+2] Cycloaddition reaction (stereoselective). 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

Trost, Barry M.; Michaelis, David J.; Charpentier, Julie; Xu, Jiayi published the artcile< Palladium-Catalyzed Allylic Alkylation of Carboxylic Acid Derivatives: N-Acyloxazolinones as Ester Enolate Equivalents>, COA of Formula: C54H42N2O2P2, the main research area is acylbenzoxazolinone allylic enol carbonate stereoselective preparation enantioselective rearrangement decarboxylation; alkenoyl benzoxazolinone enantioselective preparation; enantioselective rearrangement decarboxylation acylbenzoxazolinone allylic enol carbonate palladium phosphinylbenzamide.

Acylbenzoxazolinone allylic enol carbonates I [R = Me, Et, EtCH2, H2C:CHCH2, PhCH2, cyclohexyl, Cl(CH2)3, EtO2C(CH2)3, TBDPSO(CH2)3; R1 = H2C:CHCH2, H2C:CMeCH2, H2C:C(SiMe3)CH2, 2-cyclohexen-1-yl, (E)-PhCH:CHCH2; TBDPS = tert-butyldiphenylsilyl] underwent stereoselective rearrangement and decarboxylation in the presence of the nonracemic phosphinylbenzamide II (R2 = 2-MeC6H4) and tris(dibenzylidene)dipalladium chloroform solvate to give nonracemic alkanoyl benzoxazolinones III in 58-99% yields and in 79-99% ee [R = Me, Et, EtCH2, H2C:CHCH2, PhCH2, cyclohexyl, Cl(CH2)3, EtO2C(CH2)3, TBDPSO(CH2)3; R1 = H2C:CHCH2, H2C:CMeCH2, H2C:C(SiMe3)CH2, 2-cyclohexen-1-yl, (E)-PhCH:CHCH2 with minor regioisomeric impurities formed when R1 = (E)-PhCH:CHCH2]. III (R = Me; R1 = 2-methyl-2-propenyl) in 97% ee was converted stereoselectively to carboxylic acid and alc. derivatives (S)-R2CHMeCH2CMe:CH2 (R2 = HO2C, PhCH2OCO, PhCH2SCO, HOCH2) in 78-86% yields and with the products in 96-97% ee.

Angewandte Chemie, International Edition published new progress about Decarboxylation (stereoselective). 152140-65-3 belongs to class chiral-phosphine-ligands, and the molecular formula is C54H42N2O2P2, COA of Formula: C54H42N2O2P2.

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

Sarcher, Christian; Luehl, Anja; Falk, Florian C.; Lebedkin, Sergei; Kuehn, Michael; Wang, Cong; Paradies, Jan; Kappes, Manfred M.; Klopper, Wim; Roesky, Peter W. published the artcile< [2.2]Paracyclophanediyldiphosphane Complexes of Gold>, Electric Literature of 325168-88-5, the main research area is paracyclophanediyl diphosphine gold complex preparation crystal mol structure; alkyne hydroamination catalyst paracyclophanediyl diphosphine gold chloride complex; phosphorescence paracyclophanediyl diphosphine gold chloride complex.

Authors have prepared digold(I) complexes with the rigid-backbone diphosphine ligands PhanePhos, xyl-PhanePhos, and Ph2-GemPhos. All complexes were characterized by single-crystal x-ray diffraction, NMR, IR, Raman, and photoluminescence (PL) spectroscopy. [PhanePhos(AuCl)2] and [GemPhos(AuCl)2] show a very similar ligand scaffold, but different (aurophilic vs. nonaurophilic) intramol. Au-Au distances. Absorption and PL spectra of both compounds are quite similar. Theor. investigations reveal that the excited states are of different character (i.e., influenced by the Au-Au contacts). The resp. transition energies, however, lie close to each other, thus resulting in similar exptl. spectra. The gold atoms appear to produce a significant heavy-atom effect in the electronic relaxation dynamics. Thus, [PhanePhos(AuCl)2] and [GemPhos(AuCl)2] both show bright-green millisecond-long phosphorescence at low temperatures, although the latter is quenched at ambient temperature [PhanePhos(AuCl)2] and [GemPhos(AuCl)2] were also used as catalysts in the intra- and intermol. hydroamination of alkynes. Good to quant. conversions on a reasonable time scale were observed The overall performance of these catalysts in the studied reactions was similar, showing that Au-Au contacts do not have a major influence on the catalytic performance.

European Journal of Inorganic Chemistry published new progress about Alkynes Role: RCT (Reactant), RACT (Reactant or Reagent). 325168-88-5 belongs to class chiral-phosphine-ligands, and the molecular formula is C48H50P2, Electric Literature 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

Cederbaum, Fredrik; Lamberth, Clemens; Malan, Christophe; Naud, Fred; Spindler, Felix; Studer, Martin; Blaser, Hans-Ulrich published the artcile< Synthesis of substituted mandelic acid derivatives via enantioselective hydrogenation: Homogeneous versus heterogeneous catalysis>, Electric Literature of 325168-88-5, the main research area is stereoselective hydrogenation chlorophenylglyoxylate ruthenium homogeneous heterogeneous catalyst; chloromandelate stereoselective preparation ruthenium homogeneous heterogeneous catalyst; platinum cinchona catalyst stereoselective hydrogenation chlorophenylglyoxylate.

An extensive screening of both homogeneous and heterogeneous catalysts was carried out for the enantioselective hydrogenation of p-chlorophenylglyoxylic acid derivatives For p-chlorophenylglyoxylic amides only homogeneous Rh-diphosphine complexes gave satisfactory results, ees up to 87% were observed for the cy-oxo-pronop ligand. For Me p-chlorophenylglyoxylate both a homogeneous as well as a heterogeneous catalyst performed with ees >90%. A Pt catalyst modified with cinchona derivatives achieved 93% ee for the (R)- and 87% ee for the (S)-Me p-chloromandelate. A Ru-MeObiphep catalyst also reached 93% ee with TONs up to 4000 and TOFs up to 210 h-1. For all catalytic systems the effects of the metal, the nature of the chiral auxiliary and the solvent as well as of the reaction conditions were investigated. The homogeneous process was scaled up to the kg scale and the enantiomeric purity of the product was enhanced to >99% ee by two recrystallizations of the free p-chlorophenylmandelic acid.

Advanced Synthesis & Catalysis published new progress about Catalysts. 325168-88-5 belongs to class chiral-phosphine-ligands, and the molecular formula is C48H50P2, Electric Literature 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

Trost, Barry M.; Schultz, Johnathan E.; Bai, Yu published the artcile< Development of Chemo- and Enantioselective Palladium-Catalyzed Decarboxylative Asymmetric Allylic Alkylation of α-Nitroesters>, Name: N,N’-(11R,12R)-(9,10-Dihydro-9,10-ethanoanthracene-11,12-diyl)bis[2-(diphenylphosphino)benzamide], the main research area is acyclic nitroalkane enantioselective preparation; nitro allyl ester decarboxylative enantioselective allylic alkylation palladium catalyst; allylic alkylation; asymmetric catalysis; chemoselectivity; enantioselectivity; palladium catalysis.

We describe the development of a Pd-catalyzed decarboxylative asym. allylic alkylation of α-nitro allyl esters to afford acyclic tetrasubstituted nitroalkanes. Optimization of the reaction parameters revealed unique ligand and solvent combinations crucial for achieving chemo- and enantioselective C-alkylation of electronically challenging benzylic nitronates and sterically encumbered 2-allyl esters. Substrates were efficiently accessed in a combinatorial fashion by a cross-Claisen/ α-arylation sequence. The method provides functional group orthogonality that complements nucleophilic imine allylation strategies for α-tertiary amine synthesis.

Angewandte Chemie, International Edition published new progress about Alkanes, nitro Role: SPN (Synthetic Preparation), PREP (Preparation). 152140-65-3 belongs to class chiral-phosphine-ligands, and the molecular formula is C54H42N2O2P2, Name: 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

Trost, Barry M.; Sacchi, Karna L.; Schroeder, Gretchen M.; Asakawa, Naoyuki published the artcile< Intramolecular Palladium-Catalyzed Allylic Alkylation: Enantio- and Diastereoselective Synthesis of [2.2.2] Bicycles>, Product Details of C54H42N2O2P2, the main research area is bicyclooctanedione vinyl enantioselective diastereoselective preparation; quinuclidinone vinyl enantioselective diastereoselective preparation; cyclohexenone acetoxybutenyl intramol palladium catalyzed allylic alkylation; hydroxypyridine tetrahydro methoxycarbonylbutenyl intramol palladium catalyzed allylic alkylation.

Isomeric bicyclo[2.2.2]octan-2,3-diones I and potential precursors to quinine alkaloids quinuclidin-2-ones II were prepared both enantio- and diastereoselectively via intramol. Pd-catalyzed asym. allylic alkylation of functionalized alkenyl cyclohexenone III and tetrahydropyridine IV, resp.

Organic Letters published new progress about Allylic alkylation, stereoselective (intramol.). 152140-65-3 belongs to class chiral-phosphine-ligands, and the molecular formula is C54H42N2O2P2, Product Details of C54H42N2O2P2.

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

Toure, Momar; Chuzel, Olivier; Parrain, Jean-Luc published the artcile< Asymmetric Rhodium-Directed anti-Markovnikov Regioselective Boracyclopentannulation>, Related Products of 139139-93-8, the main research area is asym rhodium directed anti Markovnikov regioselective boracyclopentannulation; crystal mol structure allylimidazolylidene borane imidazoloboracyclopentane compound.

A Shimoi-type activation of B-H bond of NHC-boranes by a diphosphine-ligated cationic Rh complex was applied in an unprecedented intramol. hydroboration reaction of simple olefins. The use of NHC-boranes as hydroborating reagents is still undisclosed due to their nonreactivity toward alkenes which could be explained by the high stability of this complex rendering it unable to provide a “”free”” borane hydroborating reagent. B-H bond Rh activation of NHC-borane circumvents this limitation, and asym. Rh-directed anti-Markovnikov boracyclopentannulation reaction led to a library of enantioenriched cyclic boranes in high yield (up to 94%) with high regio- (up to 100%) and enantioselectivity (er up to 99.2:0.8). This new activation mode of NHC-boranes highlights their use in organometallic chem. and offers a very good approach to access chiral cyclic NHC-boranes.

Journal of the American Chemical Society published new progress about Addition reaction (anti-Markovnikov). 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