Chiral phosphine ligands

Lipshutz, Bruce H.; Lee, Ching-Tien; Taft, Benjamin R. published the artcile< A conjugate reduction pathway to chiral silanes using CuH>, Category: chiral-phosphine-ligands, the main research area is ester carboxylic silylated chiral preparation asym reduction hydrosilylation enoate; copper hydride ferrocenylphosphine catalyst asym reduction hydrosilylation enoate; silane carboxyalkyl chiral preparation asym reduction silyl enoate.

Asym. reduction of β-silyl α,β-unsaturated esters was achieved by CuH/(R,S)-PPF-P(tBu)2 reagent, affording chiral β-silylated arylalkanoate esters. β-Silyl enoates (Z)- and (E)-PhMe2SiCR:CHCO2R1 [(Z)-2, (E)-2, resp.] were prepared by Peterson or Horner-Wadsworth-Emmons olefination, resp., of the corresponding acylsilanes PhMe2SiCOR. The compounds 2 were reduced by CuH-catalyzed conjugate hydrosilylation by polymethylhydrosiloxane in the presence of chiral ferrocenylphosphine, (R,S)-1-[1-(di-tert-butylphosphino)ethyl]-2-diphenylphosphinoferrocene (1). Exptl. details concerning asym. 1,4-reduction of β-silylated-β,β-disubstituted enoates catalyzed by CuH are described.

Synthesispublished new progress about Esters, α,β-unsaturated Role: RCT (Reactant), SPN (Synthetic Preparation), RACT (Reactant or Reagent), PREP (Preparation). 277306-29-3 belongs to class chiral-phosphine-ligands, and the molecular formula is C32H40FeP2, 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

Oonishi, Yoshihiro; Hato, Yoshio; Sato, Yoshihiro published the artcile< Rhodium(I)-Catalyzed Diastereoselective Cycloisomerization of Enynes with Tethered (S)-2-Methyl-2-propanesulfinyl Imine>, Synthetic Route of 139139-93-8, 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 & Catalysispublished 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, Synthetic Route 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

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>, Recommanded Product: (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 Editionpublished 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, 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, Mark; Fagnou, Keith; Yang, Dingqiao published the artcile< Rhodium-Catalyzed Asymmetric Ring Opening Reactions of Oxabicyclic Alkenes: Application of Halide Effects in the Development of a General Process>, Recommanded Product: (2S)-1-[(1S)-1-[Bis(1,1-dimethylethyl)phosphino]ethyl]-2-(diphenylphosphino)ferrocene, the main research area is alkene oxabicyclic rhodium catalyzed asym ring opening nucleophile; naphthalenol dihydro asym synthesis; halide effect asym ring opening oxabicyclic alkene.

The halide effects in the rhodium-catalyzed asym. ring opening reaction of oxabicyclic alkenes, e.g. I, with various nucleophiles to give the corresponding dihydronaphthalenols, e.g. II [R = Et2N, 4-MeOC6H4NH, 4-methylpiperazin-1-yl, 3-indolyl, (MeO2C)2CH, 2-FC6H4O, etc.], are demonstrated. By employing halide and protic additives, the catalyst poisoning effect of aliphatic amines is reversed allowing the nucleophile to react in high yield and ee. Second, by simply changing the halide ligand on the rhodium catalyst from chloride to iodide, the reactivity and enantioselectivity of reactions employing an aromatic amine, malonate or carboxylate nucleophile are dramatically improved. Third, through the application of halide effects and more forcing reaction conditions, less reactive oxabicycle [2.2.1] substrates react to generate synthetically useful enantioenriched cyclohexenol products. Application of these new conditions to the more reactive oxabenzonorbornadiene I permits the reaction to be run with very low catalyst loadings (0.01 mol %).

Journal of the American Chemical Societypublished new progress about Alcohols, chiral Role: SPN (Synthetic Preparation), PREP (Preparation). 277306-29-3 belongs to class chiral-phosphine-ligands, and the molecular formula is C32H40FeP2, Recommanded Product: (2S)-1-[(1S)-1-[Bis(1,1-dimethylethyl)phosphino]ethyl]-2-(diphenylphosphino)ferrocene.

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

Li, Min; Li, Bin; Xia, Hong-Feng; Ye, Danru; Wu, Jing; Shi, Yifeng published the artcile< Mesoporous silica KIT-6 supported superparamagnetic CuFe2O4 nanoparticles for catalytic asymmetric hydrosilylation of ketones in air>, Application of C44H40P2, the main research area is silica copper iron oxide nanoparticle catalyst ketone asym hydrosilylation.

A diverse range of prochiral ketones were reduced in air with high yields and good-to-excellent enantioselectivities (up to 97% ee) in the presence of a heterogeneous catalyst system, which was in situ formed from catalytic amounts of superparamagnetic CuFe2O4 nanoparticles supported on mesoporous silica KIT-6 and non-racemic dipyridylphosphine ligand, the stoichiometric hydride donor polymethylhydrosiloxane (PMHS) as well as certain amounts of additives. The magnetically separable catalysts could be efficiently reused 4 times without apparent loss of both the activity and enantioselectivity.

Green Chemistrypublished new progress about Catalyst supports. 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

Mullen, Charles A.; Campbell, Alison N.; Gagne, Michel R. published the artcile< Asymmetric oxidative cation/olefin cyclization of polyenes: evidence for reversible cascade cyclization>, Quality Control of 325168-88-5, the main research area is polyenol xylylphanephos platinum silver enantioselectively diastereoselectively regioselectively oxidative cyclization; fused oxygen containing heterocycle stereoselective preparation reaction determining step.

Activation of [(xylyl-phanephos)PtCl2] by silver generates an electrophilic catalyst that can enantioselectively, diastereoselectively, and regioselectively promote the stereospecific oxidative cyclization of polyene-ols. Mechanistic experiments indicate that the stereochem.-determining step is not the initial cyclization step, but rather a subsequent step in the reaction.

Angewandte Chemie, International Editionpublished new progress about Alkenyl alcohols Role: RCT (Reactant), RACT (Reactant or Reagent). 325168-88-5 belongs to class chiral-phosphine-ligands, and the molecular formula is C48H50P2, Quality Control 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

Tsuchikama, Kyoji; Yoshinami, Yusuke; Shibata, Takanori published the artcile< Rhodium-complex-catalyzed [2+2+2] cycloaddition of diynes and carbonyl compounds>, Synthetic Route of 139139-93-8, the main research area is diyne carbonyl stereoselective cycloaddition rhodium BINAP catalyst; hydropyran stereoselective preparation electrocyclic ring opening; cyclopentene stereoselective preparation; hydropyrrole stereoselective preparation; hydrofuran stereoselective preparation.

A Rh-BINAP complex was used to catalyze the hetero-[2+2+2] cycloaddition of sym. 1,6-diynes and carbonyl moiety of keto esters, a diketone, and an aldehyde to give bicyclic α-pyrans, which were readily transformed into monocyclic compounds via the following electrocyclic ring opening. In the reaction of an unsym. 1,6-diyne and a 1,7-diyne, α-pyrans with a quaternary carbon stereocenter were obtained in moderate to excellent ee using a chiral rhodium catalyst.

Synlettpublished new progress about Alkadiynes Role: RCT (Reactant), RACT (Reactant or Reagent). 139139-93-8 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Synthetic Route 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

Trost, Barry M.; Xu, Jiayi; Schmidt, Thomas published the artcile< Palladium-Catalyzed Decarboxylative Asymmetric Allylic Alkylation of Enol Carbonates>, Application of C54H42N2O2P2, the main research area is allyl enol carbonate enantioselective regioselective decarboxylative allylic alkylation palladium; ketone homoallylic asym synthesis.

Palladium-catalyzed decarboxylative asym. allylic alkylation (DAAA) of allyl enol carbonates as a highly chemo-, regio-, and enantioselective process for the synthesis of ketones bearing either a quaternary or a tertiary α-stereogenic center has been investigated in detail. Chiral dibenzobarrelene-based diphosphine ligand was found to be optimal in the DAAA of a broad scope of cyclic and acyclic ketones including simple aliphatic ketones with more than one enolizable proton. The allyl moiety of the carbonates has been extended to a variety of cyclic or acyclic disubstituted allyl groups. The mechanistic studies revealed that, similar to the direct allylation of lithium enolates, the DAAA reaction proceeds through an “”outer sphere”” SN2 type of attack on the π-allylpalladium complex by the enolate. An important difference between the DAAA reaction and the direct allylation of lithium enolates is that in the DAAA reaction, the nucleophile and the electrophile were generated simultaneously. Since the π-allylpalladium cation must serve as the counterion for the enolate, the enolate probably exists as a tight-ion-pair. This largely prevents the common side reactions of enolates associated with the equilibrium between different enolates. The much milder reaction conditions as well as the much broader substrate scope also represent the advantages of the DAAA reaction over the direct allylation of preformed metal enolates.

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

Trost, Barry M.; Czabaniuk, Lara C. published the artcile< Palladium-Catalyzed Asymmetric Benzylation of 3-Aryl Oxindoles>, Product Details of C54H42N2O2P2, the main research area is aryloxindole enantioselective preparation; aralkyl carbonate aryloxindole asym benzylation palladium catalyst.

Palladium-catalyzed asym. benzylic alkylation with 3-aryl oxindoles as prochiral nucleophiles is reported. Proceeding analogously to asym. allylic alkylation, asym. benzylation occurs in high yield and enantioselectivity for a variety of unprotected 3-aryl oxindoles and benzylic Me carbonates using chiral bisphosphine ligands. This methodol. represents a novel asym. carbon-carbon bond formation between a benzyl group and a prochiral nucleophile to generate a quaternary center, e.g., I.

Journal of the American Chemical Societypublished new progress about Aryl aldehydes Role: RCT (Reactant), RACT (Reactant or Reagent). 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

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>, Recommanded Product: N,N’-(11R,12R)-(9,10-Dihydro-9,10-ethanoanthracene-11,12-diyl)bis[2-(diphenylphosphino)benzamide], 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 Editionpublished new progress about Decarboxylation (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