Day: October 12, 2022

Senda, Taichi; Ogasawara, Masamichi; Hayashi, Tamio published the artcile< Rhodium-Catalyzed Asymmetric 1,4-Addition of Organoboron Reagents to 5,6-Dihydro-2(1H)-pyridinones. Asymmetric Synthesis of 4-Aryl-2-piperidinones>, Recommanded Product: (R)-2,2′-Bis(diphenylphosphino)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl, the main research area is asym synthesis arylpiperidinone; stereoselective addition organoboron pyridinone; paroxetine intermediate stereoselective preparation.

Catalytic asym. synthesis of 4-aryl-2-piperidinones was realized by asym. 1,4-addition of arylboron reagents to 5,6-dihydro-2(1H)-pyridinones in the presence of a chiral bisphosphine-rhodium catalyst. In the reaction introducing the 4-fluorophenyl group, the use of 4-fluorophenylboroxine and 1 equiv (to boron) of water at 40°C gave the highest yield of the arylation product with high enantioselectivity (98% ee). The (R)-4-(4-fluorophenyl)-2-piperidinone obtained is a key intermediate for the synthesis of (-)-Paroxetine.

Journal of Organic Chemistry published new progress about Addition reaction catalysts, stereoselective. 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

Tsuchikama, Kyoji; Hashimoto, Yu-ki; Endo, Kohei; Shibata, Takanori published the artcile< Iridium-Catalyzed Selective Synthesis of 4-Substituted Benzofurans and Indoles via Directed Cyclodehydration>, Synthetic Route of 139139-93-8, the main research area is iridium catalyst aryloxy arylamino ketone cyclization benzofuran indole preparation.

A directed cyclization-dehydration cascade of α-aryloxy ketones and α-arylamino ketones was efficiently catalyzed by a cationic iridium-BINAP complex, which afforded various types of 4-substituted benzofurans and indoles in high yields with complete regioselectivity. The newly developed protocol also enabled the enantioselective preparation of chiral 4-acetyloxindole using a chiral iridium catalyst.

Advanced Synthesis & Catalysis published new progress about Cyclization. 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

Loh, Charles C. J.; Fang, Xiang; Peters, Brendan; Lautens, Mark published the artcile< Benzylic Functionalization of Anthrones via the Asymmetric Ring Opening of Oxabicycles Utilizing a Fourth-Generation Rhodium Catalytic System>, Electric Literature of 277306-29-3, the main research area is anthracene anthracenone anthrone preparation; asymmetric catalysis; dearomatization; oxabicycles; rhodium; ring opening reactions.

While anthrones exist as privileged scaffolds in bioactive mols., the enantioselective functionalization of anthrones is surprisingly scarce in the literature, with no asym. transition metal catalyzed example to date. Herein, the authors report the first asym. transition metal catalyzed benzylic functionalization of anthrones through the rhodium(I) catalyzed desymmetrization of oxabicyclic compounds As previously developed rhodium(I) systems were found to be unsuitable for this substrate, a new robust fourth-generation [Rh(cod)OH]2 based catalytic system was developed to address synthetic challenges in this protocol. Under optimized conditions the synthesis of the target compounds was achieved using bis[(1,2,5,6-η)-1,5-cyclooctadiene]di-μ-hydroxydirhodium and (2R)-1-[(1R)-1-[bis(1,1-dimethylethyl)phosphino]ethyl]-2-(diphenylphosphino)ferrocene [i.e., (R,S)-PPF-tBu2, [(R)-1-[(S)-2-(Di-tert-butylphosphino)ferrocenyl]ethyl]diphenylphosphine, JOSIPHOS SL-J 0002-1] as catalyst-ligand combination. Starting materials included 9(10H)-anthracenone derivatives and 1,4-dihydro-1,4-epoxynaphthalene derivatives The title compounds thus formed included [(hydroxy)naphthalenyl]anthracenone derivatives

Chemistry – A European Journal published new progress about Anthracenes Role: RCT (Reactant), RACT (Reactant or Reagent). 277306-29-3 belongs to class chiral-phosphine-ligands, and the molecular formula is C32H40FeP2, Electric Literature of 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

Imase, Hidetomo; Suda, Takeshi; Shibata, Yu; Noguchi, Keiichi; Hirano, Masao; Tanaka, Ken published the artcile< Highly enantioselective construction of axial chirality by palladium-catalyzed cycloisomerization of N-alkenyl arylethynylamides>, Computed Properties of 139139-86-9, the main research area is axial chiral arylpyridone derivative asym preparation; alkenyl arylethynylamide preparation asym cycloisomerization palladium phosphine; palladium chiral phosphine asym cycloisomerization catalyst.

A cationic palladium(II)/(S)-xyl-Segphos complex catalyzes enantioselective cycloisomerizations of N-alkenyl arylethynylamides leading to axially chiral 4-aryl-2-pyridones in high yields with high ee values. The present catalysis represents the first enantioselective construction of axial chirality by the transition-metal-catalyzed cycloisomerization.

Organic Letters published new progress about Cycloisomerization. 139139-86-9 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Computed Properties 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>, Safety of N,N’-(11R,12R)-(9,10-Dihydro-9,10-ethanoanthracene-11,12-diyl)bis[2-(diphenylphosphino)benzamide], 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 Letters published new progress about Allylic alkylation catalysts, stereoselective (regioselective). 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

Yamamoto, Kosuke; Qureshi, Zafar; Tsoung, Jennifer; Pisella, Guillaume; Lautens, Mark published the artcile< Combining Ru-Catalyzed C-H Functionalization with Pd-Catalyzed Asymmetric Allylic Alkylation: Synthesis of 3-Allyl-3-aryl Oxindole Derivatives from Aryl α-Diazoamides>, Recommanded Product: N,N’-(11R,12R)-(9,10-Dihydro-9,10-ethanoanthracene-11,12-diyl)bis[2-(diphenylphosphino)benzamide], the main research area is ruthenium catalyst functionalization palladium asym allylic alkylation aryl diazoamide; allylaryl oxindole stereoselective preparation.

Ruthenium-catalyzed C-H functionalization was successfully combined with palladium-catalyzed asym. allylic alkylation in one pot. The novel dual-metal-catalyzed reaction provides a variety of 3-allyl-3-aryl oxindoles from the corresponding α-diazoamides in up to 99% yield with up to 85% ee. The appropriate ligand choice is important to promote the sequential reaction, avoiding undesired metal interaction or ligand exchange.

Organic Letters 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

Araki, Tatsuya; Hojo, Daiki; Noguchi, Keiichi; Tanaka, Ken published the artcile< Enantioselective synthesis of planar chiral paracyclophanes with short ansa chains and structure of strained dioxa[7]paracyclophane>, Recommanded Product: (S)-(-)-2,2′-Bis(diphenylphosphino)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl, the main research area is paracyclophane planar chiral stereoselective preparation.

The enantioselective synthesis of planar chiral [7] and [8]paracyclophanes has been achieved by the cationic rhodium(I)-(S)-H8-BINAP complex catalyzed [2+2+2] cycloaddition Planar chiral [9]paracyclophanes were also synthesized by the same method. The X-ray crystallog. anal. of the strained dioxa[7]paracyclophane revealed the significant deformation of the benzene ring from planarity.

Synlett published new progress about Enantioselective synthesis. 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

Trost, Barry M.; Thaisrivongs, David A.; Hartwig, Jan published the artcile< Palladium-Catalyzed Asymmetric Allylic Alkylations of Polynitrogen-Containing Aromatic Heterocycles>, Computed Properties of 152140-65-3, the main research area is cyclohexenylmethyl nitrogen heterocycle enantioselective preparation; enantioselective allylic alkylation cyclohexenyl cyclopentenyl mesityl ester nitrogen heterocycle; trimethylbenzoate ester leaving group enantioselective allylic alkylation reaction.

Nonracemic cyclohexenylmethyl- and cyclopentenylmethyl-substituted nitrogen heterocycles such as I are prepared in 44-93% yields and in 75->99% ee by enantioselective allylic alkylation reactions of cyclohexenyl and cyclopentenyl trimethylbenzoates with methyl-substituted nitrogen heterocycles such as 2-methylpyrazine in the presence of bis(allylpalladium chloride) and a nonracemic dibenzamidodibenzobicyclooctane ligand. Methylated nitrogen-containing aromatic heterocycles such as 2-methylpyrazine, 2-methylpyrimidine, 3-methyl-6-phenylpyridazine, 2-methylquinoxaline, and 1-benzyl-2-methylbenzimidazole are effective reactants. 5,6,7,8-Tetrahydroquinoxaline also undergoes enantioselective allylic alkylation with a cyclohexenyl trimethylbenzoate to give cyclohexenyl tetrahydroquinoxaline II in 99% yield, >99% ee, and in 81:19 diastereoselectivity. The mesityl ester, whose steric bulk prevents competitive deacylation of the electrophile from “”hard”” nucleophiles, is introduced as a new leaving group in allylic alkylation chem. In contrast to previous studies of enantioselective allylic alkylation reactions with pyridine-based substrates, no precomplexation with a Lewis acid is required before deprotonation of the nucleophiles with LiHMDS, underscoring the relative acidity of these electron-deficient nucleophiles.

Journal of the American Chemical Society published new progress about Allylic alcohols Role: RCT (Reactant), RACT (Reactant or Reagent) (esters). 152140-65-3 belongs to class chiral-phosphine-ligands, and the molecular formula is C54H42N2O2P2, Computed Properties 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

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