Month: October 2022

Sagae, Hiromi; Noguchi, Keiichi; Hirano, Masao; Tanaka, Ken published the artcile< Rhodium-catalyzed enantio- and diastereoselective intramolecular [2 + 2 + 2] cycloaddition of unsymmetrical dienynes>, Recommanded Product: (R)-2,2′-Bis(diphenylphosphino)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl, the main research area is dienyne rhodium catalyst intramol cycloaddition; polycyclic cyclohexene derivative stereoselective preparation crystal structure; benzopyran derivative stereoselective preparation; biscyclooctadienerhodium tetrafluoroborate octahydrobinap asym cycloaddition catalyst.

A cationic rhodium(I)/(R)-H8-BINAP or (R)-Segphos complex catalyzes an intramol. [2 + 2 + 2] cycloaddition of unsym. dienynes, leading to fused tri- and tetracyclic cyclohexenes bearing two tertiary or quaternary carbon centers in high yields with high enantio- and diastereoselectivity.

Chemical Communications (Cambridge, United Kingdom)published new progress about Alkenynes Role: RCT (Reactant), SPN (Synthetic Preparation), RACT (Reactant or Reagent), PREP (Preparation) (dienynes). 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

De, Subhadip; Das, Mrinal Kanti; Roy, Avishek; Bisai, Alakesh published the artcile< Synthesis of 2-Oxindoles Sharing Vicinal All-Carbon Quaternary Stereocenters via Organocatalytic Aldol Reaction>, Name: N,N’-(11R,12R)-(9,10-Dihydro-9,10-ethanoanthracene-11,12-diyl)bis[2-(diphenylphosphino)benzamide], the main research area is oxindole preparation organocatalytic enantioselective aldol; folicanthine formal total synthesis organocatalytic enantioselective aldol.

An organocatalytic enantioselective aldol reaction using paraformaldehyde as the C1-unit has been developed for the synthesis of 2-oxindoles sharing vicinal all-carbon quaternary stereocenters. The methodol. is eventually employed in the formal total synthesis of (+)-folicanthine (I).

Journal of Organic Chemistrypublished new progress about Aldol addition catalysts, stereoselective. 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

Yang, Bo; Yang, Wu; Guo, Yonghong; You, Lijun; He, Chuan published the artcile< Enantioselective Silylation of Aliphatic C-H Bonds for the Synthesis of Silicon-Stereogenic Dihydrobenzosiloles>, Formula: C44H40P2, the main research area is rhodium catalyzed enantioselective silylation cyclization styrene derivative arylsilane; silicon stereogenic dihydrobenzosilole containing dehydrocholesterol preparation crystal structure; mol structure silicon stereogenic dihydrobenzosilole containing dehydrocholesterol; C(sp3)−H silylation; asymmetric catalysis; dihydrobenzosiloles; hydrosilylation; silanes.

A Rh(I)-catalyzed enantioselective silylation of aliphatic C-H bonds for the synthesis of Si-stereogenic dihydrobenzosiloles is demonstrated. This reaction involves a highly enantioselective intramol. C(sp3)-H silylation of dihydrosilanes, followed by a stereospecific intermol. alkene hydrosilylation leading to the asym. tetrasubstituted silanes. A wide range of dihydrosilanes and alkenes displaying various functional groups are compatible with this process, giving access to a variety of highly functionalized Si-stereogenic dihydrobenzosiloles in good to excellent yields and enantioselectivities.

Angewandte Chemie, International Editionpublished new progress about Crystal structure. 139139-86-9 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, 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

Feng, Yuting; Viereck, Peter; Li, Shi-Guang; Tsantrizos, Youla S. published the artcile< Rh(I)-catalyzed asymmetric transfer hydrogenation of α-enamidophosphonates to α-aminophosphonates>, SDS of cas: 277306-29-3, the main research area is rhodium catalyst stereoselective transfer hydrogenation enamidophosphonate mechanism; amino phosphonate preparation stereoselective library.

An asym. Rh-catalyzed transfer hydrogenation was developed for the conversion of α-enamidophosphonates to α-aminophosphonates (α-APs) using isopropanol as the hydride donor. This methodol. is amenable to a broad substrate scope. A library of structurally diverse α-APs was synthesized in moderate to good yield and enantiomeric excess, having a methylene moiety at Cβ and aryl, heteroaryl or alkyl side chains.

Tetrahedronpublished new progress about Enantioselective synthesis. 277306-29-3 belongs to class chiral-phosphine-ligands, and the molecular formula is C32H40FeP2, SDS of cas: 277306-29-3.

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

Shintani, Ryo; Duan, Wei-Liang; Hayashi, Tamio published the artcile< Rhodium-Catalyzed Asymmetric Construction of Quaternary Carbon Stereocenters: Ligand-Dependent Regiocontrol in the 1,4-Addition to Substituted Maleimides>, Electric Literature of 139139-86-9, the main research area is rhodium complex asym addition reaction regioselectivity enantioselectivity; arylboronic acid maleimide asym addition reaction.

A rhodium-catalyzed asym. 1,4-addition of arylboronic acids of formula ArB(OH)2 (Ar = Ph, 2-naphthyl, 2-methylphenyl, 4-methoxyphenyl, 4-fluorophenyl) to substituted maleimides (I; R = Et, Me, i-Pr) has been described. The regioselectivity in this reaction is controlled by the choice of ligand (dienes or bisphosphines), and 1,4-adducts with a quaternary stereocenter (II; Ar, R = same as above) can be obtained with high regio- and enantioselectivity over 1,4-adducts with a secondary carbon center (III; Ar, R = same as above) by the use of (R)-H8-BINAP (IV). For example, I (R = Et), 3.0 equiv phenylboronic acid, 2.5 mol% divinylrhodium chloride dimer, IV (Rh/ligand = 1:1), and 0.5 equiv KOH were stirred in a 10:1 mixture of dioxane and water at 50° for 3 h to give a 87:13 mixture of II (Ar = Ph, R = Et) and III (Ar = Ph, R = Et) in 98% yield.

Journal of the American Chemical Societypublished new progress about Boronic acids Role: RCT (Reactant), RACT (Reactant or Reagent) (arylboronic acids). 139139-86-9 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Electric Literature 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.; Brennan, Megan K. published the artcile< Palladium-Catalyzed Regio- and Enantioselective Allylic Alkylation of Bis Allylic Carbonates Derived from Morita-Baylis-Hillman Adducts>, Formula: C54H42N2O2P2, the main research area is Morita Baylis Hillman adduct regioselective enantioselective allylic alkylation; palladium phosphinonaphthoylaminocyclohexane catalysis regioselective enantioselective allylic alkylation; allylic carbonate regioselective enantioselective allylic alkylation palladium catalysis.

Morita-Baylis-Hillman diene adducts (e.g. (4E)-3-[(ethoxycarbonyl)oxy]-2-methylenehex-4-enoic acid Me ester) were used as substrates in the Pd-catalyzed asym. allylic alkylation reaction with O and C nucleophiles (e.g. p-methoxyphenol) in good regio- and enantioselectivity, e.g. 78 % (88 %ee) (3S,4E)-(+)-3-(4-methoxyphenoxy)-2-methylenehex-4-enoic acid Me ester (>20:1 regioisomers), using Pd2(dba)3, (1S,2S)-1,2-bis[[[2-(diphenylphosphino)naphthalen-1-yl]carbonyl]amino]cyclohexane and tetrabutylammonium triphenyldifluorosilicate as catalyst system in DME at 25°.

Organic Letterspublished new progress about Allylic alkylation catalysts, stereoselective (regioselective). 152140-65-3 belongs to class chiral-phosphine-ligands, and the molecular formula is C54H42N2O2P2, 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

Masutomi, Koji; Sakiyama, Norifumi; Noguchi, Keiichi; Tanaka, Ken published the artcile< Rhodium-Catalyzed Regio-, Diastereo-, and Enantioselective [2+2+2] Cycloaddition of 1,6-Enynes with Acrylamides>, Synthetic Route of 139139-86-9, the main research area is enyne enantioselective diastereoselective regioselective cycloaddition acrylamide rhodium BINAP catalyst; isoindole indene isobenzofuran amide hexahydro enantioselective diastereoselective synthesis.

A variety of partially hydrogenated isoindoles I [X = NTs; R1 = H, Me, Ph; R2 = H, Me, Et, Ph; R3 = R4 = Me, n-Bu, Ph; R3 = Me, R4 = MeO, Ph; R3R4 = (CH2)4] and their carbocyclic I [X = (MeO2C)2C; R1 = R2 = R3 = Me; R4 = Ph] and oxacyclic analogs I (X = O; R1 = n-pentyl; R2 = R3 = Me; R4 = Ph) was synthesized by rhodium(I)/(R)-H8-BINAP-catalyzed asym. [2 + 2 + 2] cycloaddition of 1,6-enynes II with acrylamides H2C:CHC(O)NR3R4. In this catalysis, regioselective insertion of acrylamide into a rhodacyclopentene intermediate and the coordination of the carbonyl group of acrylamide to the cationic rhodium center suppress the undesired β-hydride elimination.

Angewandte Chemie, International Editionpublished new progress about Alkenynes Role: RCT (Reactant), RACT (Reactant or Reagent). 139139-86-9 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Synthetic Route 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

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