Month: December 2022

Catalytic asymmetric de novo construction of dihydroquinazolinone scaffolds via enantioselective decarboxylative [4+2] cycloadditions was written by Lu, Yi-Nan;Lan, Jin-Ping;Mao, Yu-Jia;Wang, Ye-Xin;Mei, Guang-Jian;Shi, Feng. And the article was included in Chemical Communications (Cambridge, United Kingdom) in 2018.Safety of (11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine This article mentions the following:

The first de novo construction of enantioenriched dihydroquinazolinones via an intermol. strategy was established. This approach also represented the first catalytic asym. [4+2] cycloaddition of vinyl benzoxazinanones with sulfonyl isocyanates, which afforded chiral dihydroquinazolinones in high yields and excellent enantioselectivities (up to 98% yield, 99 : 1 er). This reaction not only confronts the great challenge in de novo construction of enantioenriched dihydroquinazolinone skeletons, but also advances the chem. of decarboxylative cycloadditions involving vinyl benzoxazinanones. In the experiment, the researchers used many compounds, for example, (11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine (cas: 252288-04-3Safety of (11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine).

(11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine (cas: 252288-04-3) belongs to chiral phosphine ligands. Although many reactions require more nucleophilic trialkylphosphines as catalysts, only a few chiral trialkylphosphines are available. Trivalent phosphorus compounds called phosphines have a tetrahedral electron-group geometry which makes them structurally analogous to amines.Safety of (11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Catalytic Enantioselective Cloke-Wilson Rearrangement was written by Ortega, Alesandere;Manzano, Ruben;Uria, Uxue;Carrillo, Luisa;Reyes, Efraim;Tejero, Tomas;Merino, Pedro;Vicario, Jose L.. And the article was included in Angewandte Chemie, International Edition in 2018.Quality Control of (11bS)-4-Hydroxy-2,6-di(phenanthren-9-yl)dinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepine 4-oxide This article mentions the following:

Racemic cyclopropyl ketones undergo enantioselective rearrangement to deliver the corresponding dihydrofurans in the presence of a chiral phosphoric acid as the catalyst. The reaction involves activation of the donor-acceptor cyclopropane substrate by the chiral Bronsted acid catalyst to promote the ring-opening event, thus generating a carbocationic intermediate that subsequently undergoes cyclization. Computational studies and control experiments support this mechanistic pathway. In the experiment, the researchers used many compounds, for example, (11bS)-4-Hydroxy-2,6-di(phenanthren-9-yl)dinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepine 4-oxide (cas: 1043567-32-3Quality Control of (11bS)-4-Hydroxy-2,6-di(phenanthren-9-yl)dinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepine 4-oxide).

(11bS)-4-Hydroxy-2,6-di(phenanthren-9-yl)dinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepine 4-oxide (cas: 1043567-32-3) belongs to chiral phosphine ligands. Phosphine-catalyzed asymmetric reactions are now powerful and versatile tools for the construction of C–C, C–N, C–O, and C–S bonds and for the syntheses of functionalized carbocycles and heterocycles. Chiral phosphine catalysts: Nucleophilic phosphine catalysis often involves the formation of Lewis adducts, namely phosphonium (di)enolate zwitterions, as reaction intermediates.Quality Control of (11bS)-4-Hydroxy-2,6-di(phenanthren-9-yl)dinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepine 4-oxide

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Application of chiral anion metathesis strategy in asymmetric transfer hydrogenation of isoquinolines was written by Shi, Lei;Ji, Yue;Huang, Wenxue;Zhou, Yonggui. And the article was included in Huaxue Xuebao in 2014.Name: (11bS)-4-Hydroxy-2,6-di(phenanthren-9-yl)dinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepine 4-oxide This article mentions the following:

Asym. hydrogenation of N-hetero aromatics offers a very straightforward and efficient method to obtain the corresponding chiral N-hetero cyclic saturated or partially saturated compounds As one of the most challenging substrates, asym. hydrogenation of isoquinolines has met with limited success probably because of lower reactivity and the catalyst deactivation resulted from strong coordination. Considering the prevalence of the chiral 1,2,3,4-tetrahydroisoquinoline motif in natural alkaloids and drug mols., the development of new catalyst system for asym. hydrogenation of isoquinolines is highly desirable and significant. Herein, a novel chiral anion metathesis strategy successfully applied for asym. transfer hydrogenation of isoquinolines is reported. N-Protected 1-substituted 1,2-dihydroisoquinolines were obtained with high yield and up to 79% ee in the presence of Hantzsch ester and chloroformate using chiral phosphoric acid as catalyst. The phosphate salt and the activated N-acyl isoquinolinium chloride undergo anion metathesis to form chiral contact ion pair, which leads to a highly enantioselective transfer hydrogenation of isoquinolines. After systematically investigating the effects of activating reagent, solvent, base, hydride donor and catalyst on this transfer hydrogenation reaction, the best result was achieved under the optimized condition as follows: 5 mol% H8-BINOL-derived chiral phosphoric acid as catalyst, 1.2 equiv 2,2,2-trichloroethyl chloroformate as activator, 1.5 equiv di-Me 2,6-diethyl-1,4-dihydropyridine-3,5-dicarboxylate as hydride donor, 1.5 equiv sodium carbonate as base and cyclohexane as solvent. The reaction is tolerant toward a broad range of aryl or alkyl 1-substituted isoquinoline substrates. This methodol. represents one of the rare examples of asym. hydrogenation of this challenging substrate. The utilizing of chiral anion metathesis strategy could enable chiral phosphoric acid to catalyze more asym. transformation process and further researching is ongoing in our laboratory In the experiment, the researchers used many compounds, for example, (11bS)-4-Hydroxy-2,6-di(phenanthren-9-yl)dinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepine 4-oxide (cas: 1043567-32-3Name: (11bS)-4-Hydroxy-2,6-di(phenanthren-9-yl)dinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepine 4-oxide).

(11bS)-4-Hydroxy-2,6-di(phenanthren-9-yl)dinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepine 4-oxide (cas: 1043567-32-3) belongs to chiral phosphine ligands. During the past two decades, tertiary phosphine catalysts have been applied extensively in a wide range of carbon–carbon and carbon–heteroatom bond-forming transformations. Indeed, very little research on chiral tertiary phosphine-catalyzed asymmetric reactions occurred prior to the year 2000.Name: (11bS)-4-Hydroxy-2,6-di(phenanthren-9-yl)dinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepine 4-oxide

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Rhodium-catalyzed enantioselective 1,4-additions of arylboronic acids to substituted enones was written by Mediavilla Urbaneja, Laura;Krause, Norbert. And the article was included in Tetrahedron: Asymmetry in 2006.Formula: C24H22NO2P This article mentions the following:

The rhodium-catalyzed enantioselective 1,4-addition of (aryl)boronic acids to bifunctional Michael acceptors in the presence of phosphoramidite ligands occurs regioselectively at the endocyclic carbon-carbon double bond and in up to 95% ee. The presence of KOH is required to increase the reactivity so that less boronic acid and lower reaction temperatures can be used. The corresponding addition to a chiral enone (i.e., 6-methyl-2-cyclohexen-1-one) takes place with epimerization of the product to the thermodynamically more stable trans-isomer, which was obtained with up to 98% ee. In the experiment, the researchers used many compounds, for example, (11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine (cas: 252288-04-3Formula: C24H22NO2P).

(11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine (cas: 252288-04-3) belongs to chiral phosphine ligands. At present, the synthesis of new chiral phosphines designed specifically for nucleophilic organocatalysis remains a significant challenge. Asymmetric catalytic performance is determined not only by the metal center but also by the chiral ligand selected.Formula: C24H22NO2P

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

PipPhos and MorfPhos: Privileged Monodentate Phosphoramidite Ligands for Rhodium-Catalyzed Asymmetric Hydrogenation was written by Bernsmann, Heiko;van den Berg, Michel;Hoen, Rob;Minnaard, Adriaan J.;Mehler, Gerlinde;Reetz, Manfred T.;de Vries, Johannes G.;Feringa, Ben L.. And the article was included in Journal of Organic Chemistry in 2005.Formula: C24H22NO2P This article mentions the following:

Chiral nonracemic monodentate phosphoramidites having binaphthalene and octahydrobinaphthalene backbones were prepared and showed excellent enantioselectivity in rhodium-catalyzed asym. hydrogenation of dehydroamino acids, itaconic acid and enamides. Reaction of (S)-1,1′-binaphthalene-2,2′-diol, (S)-C₂₀H₁₂(OH)₂ and (S)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthalene-2,2′-diol, (S)-C₂₀H₂₀(OH)₂ with PCl₃ and HNR₂ afforded a library of 20 monodentate phosphoramidite ligands (S)-C₂₀H₁₂O₂PNR₂ and (S)-C₂₀H₂₀O₂PNR₂ (1a–13a and 1b–11b, resp., R = Me, Et, n-Pr or R₂ = pyrrolidino, piperidino, hexahydro-1H-azepin-1-yl, morpholino, thiomorpholino, 4-phenyl-piperazin-1-yl, 1-indolinyl, 1,2,3,4-tetrahydro-2-isoquinolinyl, 2-alkoxycarbonyl-1-pyrrolidino). Asym. hydrogenation of Me 2-acetamidoacrylate, Me 2-acetamidocinnamate, di-Me itaconate and a number of N-acetyl enamines catalyzed by composition of [(cod)₂Rh]BF₄ and the phosphoramidites proceeds with high conversion and ee; specifically two ligands, PipPhos and MorfPhos [(S)-C₂₀H₁₂O₂PNR₂ R₂ = piperidino and morpholino, resp.] afford excellent and in several cases unprecedented enantioselectivities. In the experiment, the researchers used many compounds, for example, (11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine (cas: 252288-04-3Formula: C24H22NO2P).

(11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine (cas: 252288-04-3) belongs to chiral phosphine ligands. During the past two decades, tertiary phosphine catalysts have been applied extensively in a wide range of carbon–carbon and carbon–heteroatom bond-forming transformations. Asymmetric catalytic performance is determined not only by the metal center but also by the chiral ligand selected.Formula: C24H22NO2P

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Nickel-Catalyzed Asymmetric Ullmann Coupling for the Synthesis of Axially Chiral Tetra-ortho-Substituted Biaryl Dials was written by Chen, Wen-Wen;Zhao, Qian;Xu, Ming-Hua;Lin, Guo-Qiang. And the article was included in Organic Letters in 2010.Name: (11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine This article mentions the following:

The first example of nickel-catalyzed asym. Ullmann coupling of bis-ortho-substituted aryl bromides is described. With the chiral BINOL-based monodentate phosphoramidite ligand I, the reaction allows atropoenantioselective synthesis of a series of axially chiral tetra-ortho-substituted biaryl dials. By taking advantage of this asym. Ullmann coupling as a key stereogenic axis-forming reaction, the formal synthesis of (+)-isoschizandrin was accomplished. In the experiment, the researchers used many compounds, for example, (11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine (cas: 252288-04-3Name: (11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine).

(11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine (cas: 252288-04-3) belongs to chiral phosphine ligands. During the past two decades, tertiary phosphine catalysts have been applied extensively in a wide range of carbon–carbon and carbon–heteroatom bond-forming transformations. Most of these phosphines are acyclic, usually possess low nucleophilic activity, and generally display poor enantioselectivities for phosphine organocatalysis. Name: (11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Construction of Spiro-tetrahydroquinolines via Intramolecular Dearomatization of Quinolines: Free of a Preinstalled Activation Group was written by Wang, Shou-Guo;Zhang, Wei;You, Shu-Li. And the article was included in Organic Letters in 2013.Name: (11bS)-4-Hydroxy-2,6-di(phenanthren-9-yl)dinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepine 4-oxide This article mentions the following:

A highly efficient synthesis of spiro-tetrahydroquinolines (up to 99% yield) has been realized via cascade hydrogenative dearomatization of quinoline and intramol. aza-Friedel-Crafts alkylation reaction. In the experiment, the researchers used many compounds, for example, (11bS)-4-Hydroxy-2,6-di(phenanthren-9-yl)dinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepine 4-oxide (cas: 1043567-32-3Name: (11bS)-4-Hydroxy-2,6-di(phenanthren-9-yl)dinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepine 4-oxide).

(11bS)-4-Hydroxy-2,6-di(phenanthren-9-yl)dinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepine 4-oxide (cas: 1043567-32-3) belongs to chiral phosphine ligands. Although many reactions require more nucleophilic trialkylphosphines as catalysts, only a few chiral trialkylphosphines are available. Indeed, very little research on chiral tertiary phosphine-catalyzed asymmetric reactions occurred prior to the year 2000.Name: (11bS)-4-Hydroxy-2,6-di(phenanthren-9-yl)dinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepine 4-oxide

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Asymmetric iridium-catalyzed hydrogenation of 2-methylindole using phosphite ligands was written by Lyubimov, Sergey E.;Ozolin, Dmitry V.;Davankov, Vadim A.. And the article was included in Tetrahedron Letters in 2014.Synthetic Route of C24H22NO2P This article mentions the following:

The iridium-catalyzed asym. hydrogenation of 2-methylindole using monodentate phosphites and amidophosphites as ligands was examined The use of iodine as the additive resulted in increased enantioselectivity and conversion in the iridium-catalyzed hydrogenation of 2-methylindole. Full conversion and up to 80% ee were obtained with a catalyst based on a phosphite ligand. In the experiment, the researchers used many compounds, for example, (11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine (cas: 252288-04-3Synthetic Route of C24H22NO2P).

(11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine (cas: 252288-04-3) belongs to chiral phosphine ligands. The synthesis of novel trialkylphosphines can be quite difficult, thereby limiting the scope of their chiral variants. Effective chiral catalysts for nucleophilic phosphine catalysis are scarce, seriously limiting the development of asymmetric variants. Synthetic Route of C24H22NO2P

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Asymmetric allylation of aryl aldehydes: studies on the scope and mechanism of the palladium catalyzed diethylzinc mediated umpolung using phosphoramidite ligands was written by Howell, Gareth P.;Minnaard, Adriaan J.;Feringa, Ben L.. And the article was included in Organic & Biomolecular Chemistry in 2006.Safety of (11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine This article mentions the following:

Using modular, monodentate phosphoramidite ligands, enantioselective palladium catalyzed diethylzinc mediated allylation of aldehydes was achieved. The scope of the asym. C-C bond formation was investigated with respect to nucleophilic and electrophilic components and an alternative reaction mechanism is proposed based on our findings. In the experiment, the researchers used many compounds, for example, (11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine (cas: 252288-04-3Safety of (11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine).

(11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine (cas: 252288-04-3) belongs to chiral phosphine ligands. The synthesis of novel trialkylphosphines can be quite difficult, thereby limiting the scope of their chiral variants. Effective chiral catalysts for nucleophilic phosphine catalysis are scarce, seriously limiting the development of asymmetric variants. Safety of (11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Enantioselective synthesis of (3-indolyl)glycine derivatives via asymmetric Friedel-Crafts reaction between indoles and glyoxylate imines was written by Kang, Qiang;Zhao, Zhuo-An;You, Shu-Li. And the article was included in Tetrahedron in 2009.Quality Control of (11bS)-4-Hydroxy-2,6-di(phenanthren-9-yl)dinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepine 4-oxide This article mentions the following:

Chiral phosphoric acid-catalyzed enantioselective Friedel-Crafts reaction of indoles with Et glyoxylate imines was developed. With 10 mol% of the catalyst, the Friedel-Crafts reactions between a wide range of indoles and imines have been carried out, affording optically active (3-indolyl)glycine derivatives with excellent yields and high enantioselectivities (up to 87% ee). In the experiment, the researchers used many compounds, for example, (11bS)-4-Hydroxy-2,6-di(phenanthren-9-yl)dinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepine 4-oxide (cas: 1043567-32-3Quality Control of (11bS)-4-Hydroxy-2,6-di(phenanthren-9-yl)dinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepine 4-oxide).

(11bS)-4-Hydroxy-2,6-di(phenanthren-9-yl)dinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepine 4-oxide (cas: 1043567-32-3) belongs to chiral phosphine ligands. During the past two decades, tertiary phosphine catalysts have been applied extensively in a wide range of carbon–carbon and carbon–heteroatom bond-forming transformations. Asymmetric catalytic performance is determined not only by the metal center but also by the chiral ligand selected.Quality Control of (11bS)-4-Hydroxy-2,6-di(phenanthren-9-yl)dinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepine 4-oxide

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis