Month: October 2022

Mao, Menglei; Zhai, Tingting; Meng, Lingding; Meng, Zihui; Liu, Wenfang published the artcile< Controllable preparation of mesoporous silica and its application in enzyme-catalyzed CO2 reduction>, Application of C21H27N7Na2O14P2, the main research area is controllable mesoporous silica enzyme catalyzed CO2 reduction.

Enzymic conversion of CO2 to high-value chems. is a significant route for the utilization of greenhouse gases in mild, high-selectivity and environment-friendly way, however, conversion efficiency is not yet satisfying. Here, mesoporous silica (mSiO2) nanoparticles with controllable structure were prepared and modified by polydopamine (PDA) and polyethyleneimine (PEI), which were then used in an integrated process for CO2 capture and conversion to formate for the first time. The effects of structure parameters of mSiO2 and modification conditions on its application properties were investigated. The results show that in a range of 230 ∼ 500 nm, SiO2 particles with smaller size exhibited better intensifying effect, while the optimal size was 410 nm for mSiO2 with the same etching extent, attributed to a higher sp. surface area. mSiO2 itself was a robust CO2 adsorbent and the addition of 0.01 g mSiO2(410) enabled CO2 conversion to be accelerated 11.94 times compared to free enzyme. After modification, with 0.05 g PDA/PEI-mSiO2(340) and PDA/PEI-mSiO2(410), the enzyme reaction was expedited up to 24 and 30.8 times of the system without particles due to an enhanced CO2 uptake, as a collaborative result of mesoporous structure and amino-functionalization. Following that, PDA/PEI-mSiO2(410) was used as the carrier for the co-immobilization of formate dehydrogenase and carbonic anhydrase, which could retain 86.7% activity after use for 10 times and 55.2% activity after 21 days at 4°C, while 29.6% for free enzymes.

Chemical Engineering Journal (Amsterdam, Netherlands) published new progress about Adsorbents. 606-68-8 belongs to class chiral-phosphine-ligands, and the molecular formula is C21H27N7Na2O14P2, Application 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

Yen, Andy; Choo, Ken-Loon; Yazdi, Shabnam K.; Franke, Patrick T.; Webster, Robert; Franzoni, Ivan; Loh, Charles C. J.; Poblador-Bahamonde, Amalia I.; Lautens, Mark published the artcile< Rhodium-Catalyzed Enantioselective Isomerization of meso-Oxabenzonorbornadienes to 1,2-Naphthalene Oxides>, Application In Synthesis of 277306-29-3, the main research area is epoxynaphthalene enantioselective preparation; methoxy hydronaphthalenol enantioselective preparation; rhodium phenylphosphinoferrocenylethylphosphine catalyst enantioselective isomerization oxabicycloheptenedimethanol ester benzyl ether; enantioselective isomerization ring opening oxabicycloheptene methanol rhodium phenylphosphinoferrocenylethylphosphine catalyst; mechanism stereoselectivity isomerization ring opening oxabicycloheptene rhodium phenylphosphinoferrocenylethylphosphine catalyst; acetoxymethyl bromobenzyloxymethyl epoxynaphthalene mol crystal structure; allylic compounds; asymmetric catalysis; enantioselectivity; isomerization; rhodium.

In the presence of Rh(cod)2BF4 and nonracemic diphenylphosphinoferrocenylethylphosphines, oxabicycloheptenedimethanol esters and dibenzyl ethers such as I underwent enantioselective isomerization to yield nonracemic 1,2-epoxynaphthalenes such as II in 53-99% yields and in 95->99% ee. In the presence of Rh(cod)2BF4 and a nonracemic diphenylphosphinoferrocenylethylphosphine, I and II underwent ring opening or tandem isomerization and ring opening reactions to yield methoxydihydronaphthalenols such as III. DFT calculations were performed to account for the stereoselectivities of the isomerization and ring opening reactions; ring-opening reactions of bridgehead disubstituted oxabicyclic alkenes proceed through the intermediacy of 1,2-epoxynaphthalenes and may indicate a kinetically and thermodynamically favored reductive elimination as the origin for the observed enantioselectivities. The structures of II and of a bis(bromobenzyloxymethyl) 1,2-epoxynaphthalene were determined by X-ray crystallog.

Angewandte Chemie, International Edition published new progress about Aralkyl alcohols Role: SPN (Synthetic Preparation), PREP (Preparation). 277306-29-3 belongs to class chiral-phosphine-ligands, and the molecular formula is C32H40FeP2, Application In Synthesis 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

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