Category: chiral-phosphine-ligands

Asymmetric C-H functionalization of indoles via enantioselective protonation was written by Qiu, Huang;Zhang, Dan;Liu, Shunying;Qiu, Lin;Zhou, Jun;Qian, Yu;Zhai, Changwei;Hu, Wenhao. And the article was included in Huaxue Xuebao in 2012.Electric Literature of C48H29O4P This article mentions the following:

Asym. C-H functionalization of indoles from Rh₂(OAc)₄ and chiral phosphoric acid co-catalyzed reactions of aryl diazoacetates with indoles has been investigated. Through mechanistic study regarding to the proton transfer pathway of the C-H functionalization of indoles, a new strategy to achieve the asym. C-H functionalization of indoles from metal carbenoids via enantioselective protonation has been proposed. We initially carried out a deuterium isotope experiments in order to obtain more insight into the proton transfer process of the C-H functionalization of indoles, and the experiments indicated an indirect proton transfer in the reaction. A proton-transfer shuttle such as H₂O was needed to complete the reaction. The observation provides us an opportunity to design a chiral proton-transfer shuttle to achieve the asym. C-H functionalization. In this paper, Rh₂(OAc)₄ catalyzed diazo decomposition of a aryl diazoacetate generates a metal carbenoid. Reaction of the metal carbenoid with an indole at C-3 position generates a zwitterionic intermediate. A bifunctional chiral phosphoric acid serves as a chiral proton shuttle and helps the proton transfer process via an enantioselective protonation to finish the reaction in high yield and enantioselectivity. A number of indoles including N-alkyl, aryl, silyl and a number of a-aryl-a-diazoesters are well tolerated under the established catalytic conditions, providing good to high enantioselectivity (up to 94% ee) in excellent yield (up to 99% yield). A representative procedure for the enantioselective C-H functionalization of indoles is as following: A mixture of 6-chloro-N-methylindole (1e) (41 mg, 0.25 mmol), transition metal catalyst Rh₂(OAc)₄ (1 mg, 0.0025 mmol, 1 mol%), chiral phosphoric acid co-catalyst (R)-4j (3.8 mg, 0.005 mmol, 2 mol%) and 4 Å MS (100 mg) in 1 mL of toluene was stirred at the 0°C. Me phenyl(diazo)acetate (2a) (53 mg, 0.3 mmol) in 1 Ml of toluene was added over 1 h period of time via a syringe pump. After completion of the addition, the reaction was stirred for addnl. 5 min at the same temperature Solvent was evaporated under reduced pressure to give corresponding crude product, I. The crude product was purified by flask chromatog. on silica gel (eluent: EtOAc/light petroleum ether, V : V = 1 : 40 ∼ 1 : 10) to give the pure product 3q in 92% yield with 94% 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: 1043567-32-3Electric Literature of C48H29O4P).

(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. Thousands of arylphosphines have been used as chiral ligands for metal-catalyzed asymmetric reactions. Trivalent phosphorus compounds called phosphines have a tetrahedral electron-group geometry which makes them structurally analogous to amines.Electric Literature of C48H29O4P

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Catalytic Asymmetric Conjugate Addition of a Borylalkyl Copper Complex for Chiral Organoboronate Synthesis was written by Jang, Won Jun;Yun, Jaesook. And the article was included in Angewandte Chemie, International Edition in 2019.Product Details of 252288-04-3 This article mentions the following:

The authors report the catalytic enantioselective conjugate addition of a borylalkyl Cu nucleophile generated in situ from a 1,1-diborylmethane derivative to α,β-unsaturated diesters. In the presence of a chiral N-heterocyclic carbene (NHC)-Cu catalyst, this method facilitated the enantioselective incorporation of a CH₂Bpin moiety at the β-position of the diesters to yield β-chiral alkyl boronates in up to 86% yield with high enantioselectivity. The alkylboron moiety in the resulting chiral diester products was converted into various functional groups by organic transformation of the C-B bond. 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: 252288-04-3Product Details of 252288-04-3).

(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. Generally, the efficiency of nucleophilic phosphine catalysis often depends on the nature of the tertiary phosphine. Trivalent phosphorus compounds called phosphines have a tetrahedral electron-group geometry which makes them structurally analogous to amines.Product Details of 252288-04-3

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Formal Asymmetric Organocatalytic [3+2] Cyclization between Enecarbamates and 3-Indolylmethanols: Rapid Access to 3-Aminocyclopenta[b]indoles was written by Lebee, Clement;Kataja, Antti O.;Blanchard, Florent;Masson, Geraldine. And the article was included in Chemistry – A European Journal in 2015.Category: chiral-phosphine-ligands This article mentions the following:

A highly enantio- and diastereoselective synthesis of 3-aminocyclopenta[b]indoles I [R¹ = Me, Et, CHMe₂, cyclopropyl, CH₂CHMe(CH₂)₂CH:CMe₂-(S), (CH₂)₃OSiPh₂CMe₃, R² = CH₂Ph, R³ = Ph, R⁴ = R⁵ = H; R¹ = Me, R² = CMe₃, R³ = Ph, R⁴ = R⁵ = H; R¹ = Me, R² = CH₂Ph, R³ = C₆H₄F-4, C₆H₄F-3, C₆H₄F-2, C₆H₄CF₃-4, C₆H₄OMe-3, 2-naphthyl, 2-thienyl, CHMe₂, Bu, R⁴ = R⁵ = H; R¹ = Me, R² = CH₂Ph, R³ = Ph, R⁴ = OMe-5, Br-5, Br-6, R⁵ = H; R¹ = Me, R² = R⁵ = CH₂Ph, R³ = Ph, R⁴ = H] has been developed through formal [3+2] cycloaddition reaction of enecarbamates, (E)-R¹CH:CHCO₂R², and 3-indolylmethanols, II. This transformation is catalyzed by a chiral phosphoric acid that achieves simultaneous activation of both partners of the cycloaddition Mechanistic data are also presented that suggest that the reaction occurs through a stepwise 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: 1043567-32-3Category: chiral-phosphine-ligands).

(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. Asymmetric catalytic performance is determined not only by the metal center but also by the chiral ligand selected.Category: chiral-phosphine-ligands

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Enantioselective Synthesis of Tetrahydroindolizines via Ruthenium-Chiral Phosphoric Acid Sequential Catalysis was written by Zhou, Yong;Liu, Xiao-Wei;Gu, Qing;You, Shu-Li. And the article was included in Synlett in 2016.Computed Properties of C48H29O4P This article mentions the following:

A chiral phosphoric acid and a ruthenium complex were found to catalyze an olefin cross-metathesis-asym. intramol. Friedel-Crafts alkylation of N-tethered olefin pyrroles and conjugated enones to provide a variety of chiral tetrahydroindolizine derivatives in moderate to good yields and enantioselectivity (up to 93% ee). Under optimized conditions the synthesis of the target compounds was achieved using (11bS)-4-hydroxy-2,6-bis(9-phenanthrenyl)dinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin 4-oxide (i.e., chiral cyclic phosphate analog) and [1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro[[5-[(dimethylamino)sulfonyl]-2-(1-methylethoxy-κO)phenyl]methylene-κC]ruthenium (i.e., Zhan-1B) as ligand and catalyst combination. The synthesis of the target compounds was achieved by a reaction of 1-(4-pentenyl)-2-phenyl-1H-pyrrole derivatives with 1-phenyl-2-propen-1-one derivatives, 3-Buten-2-one, (2E)-1-phenyl-2-buten-1-one. The tilte compounds thus formed included a chiral pyrrolo[1,2-d][1,4]oxazepine derivative and (indolizinyl)(aryl)ethanone derivatives 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: 1043567-32-3Computed Properties of C48H29O4P).

(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. Chiral phosphine catalysts: Nucleophilic phosphine catalysis often involves the formation of Lewis adducts, namely phosphonium (di)enolate zwitterions, as reaction intermediates.Computed Properties of C48H29O4P

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

A Novel Method for Synthesizing N-Alkoxycarbonyl Aryl α-Imino Esters and Their Applications in Enantioselective Transformations was written by Qian, Yu;Jing, Changcheng;Zhai, Changwei;Hu, Wen-hao. And the article was included in Advanced Synthesis & Catalysis in 2012.Safety 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:

A new strategy for the synthesis of N-alkoxycarbonyl aryl α-imino esters in the presence of dirhodium tetraacetate [Rh₂(OAc)₄] is reported to produce the desired compounds in high yield (up to 96%) under mild reaction conditions. The application of the synthetic method is demonstrated in enantioselective reduction and Friedel-Crafts reaction of indoles to afford the corresponding chiral arylglycines and indole derivatives, resp., in high yield and excellent 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: 1043567-32-3Safety 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. Many phosphine-catalyzed reactions have been developed for the syntheses of various biologically important acyclic and cyclic molecules. Asymmetric variants of these reactions have evolved relatively slowly. Asymmetric catalytic performance is determined not only by the metal center but also by the chiral ligand selected.Safety 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

Catalytic asymmetric synthesis of N-substituted tetrahydroquinoxalines via regioselective Heyns rearrangement and stereoselective transfer hydrogenation in one pot was written by Huang, Jin;Li, Guang-xun;Yang, Gao-feng;Fu, Ding-qiang;Nie, Xiao-kang;Cui, Xin;Zhao, Jin-zhong;Tang, Zhuo. And the article was included in Chemical Science in 2021.HPLC of Formula: 1043567-32-3 This article mentions the following:

N-Substituted tetrahydroquinoxalines (37 examples) were step-economically obtained in good yield (<97%) and ee (<99%) with readily available substrates. The reaction proceeded through an interesting regioselective Heyns rearrangement/enantioselective transfer hydrogenation in one pot. The substrate scope and the reaction mechanism were systematically investigated. 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: 1043567-32-3HPLC of Formula: 1043567-32-3).

(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. Trivalent phosphorus compounds called phosphines have a tetrahedral electron-group geometry which makes them structurally analogous to amines.HPLC of Formula: 1043567-32-3

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Palladium-catalyzed asymmetric [3 + 3] cycloaddition of trimethylenemethane derivatives with nitrones was written by Shintani, Ryo;Park, Soyoung;Duan, Wei-Liang;Hayashi, Tamio. And the article was included in Angewandte Chemie, International Edition in 2007.Recommanded Product: (11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine This article mentions the following:

Functionalized 1,2-oxazines can be obtained in high yield by a palladium-catalyzed asym. [3 + 3] cycloaddition of trimethylenemethane derivatives with nitrones. The use of a modified phosphoramidite ligand has led to the formation of these compounds with high stereoselectivity (see scheme, Cp = cyclopentadienyl). 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: 252288-04-3Recommanded Product: (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. Generally, the efficiency of nucleophilic phosphine catalysis often depends on the nature of the tertiary phosphine. Chiral ligands coordinate to metal centers to create an asymmetric environment around the reaction centers, which eventually affects enantioselectivity and reaction rate.Recommanded Product: (11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Diastereoselectively switchable enantioselective trapping of carbamate ammonium ylides with imines was written by Jiang, Jun;Xu, Hua-Dong;Xi, Jian-Bei;Ren, Bai-Yan;Lv, Feng-Ping;Guo, Xin;Jiang, Li-Qin;Zhang, Zhi-Yong;Hu, Wen-Hao. And the article was included in Journal of the American Chemical Society in 2011.Computed Properties of C48H29O4P This article mentions the following:

The diastereoselectively switchable enantioselective trapping of protic carbamate ammonium ylides with imines is reported. The intriguing Rh₂(OAc)₄ and chiral Bronsted acid cocatalyzed three-component Mannich-type reaction of a diazo compound, a carbamate, and an imine provides rapid and efficient access to both syn- and anti-α-substituted α,β-diamino acid derivatives e. g., I and II with a high level control of chemo-, diastereo-, and enantioselectivity. 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: 1043567-32-3Computed Properties of C48H29O4P).

(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.Computed Properties of C48H29O4P

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Chiral Norbornadienes as Efficient Ligands for the Rhodium-Catalyzed Asymmetric 1,4-Addition of Arylboronic Acids to Fumaric and Maleic Compounds was written by Shintani, Ryo;Ueyama, Kazuhito;Yamada, Ichiro;Hayashi, Tamio. And the article was included in Organic Letters in 2004.Recommanded Product: 252288-04-3 This article mentions the following:

A rhodium-catalyzed asym. 1,4-addition of arylboronic acids to fumaric and maleic compounds has been developed. While phosphorus-based chiral ligands fail to induce high stereoselectivity, chiral norbornadiene ligands have proved to be uniquely effective to achieve high enantioselectivity in these 1,4-addition reactions. In an example reaction, di-tert-Bu fumarate reacted with phenylboronic acid in the presence of (1R,4R)-2,5-di(2,4,6-trimethylphenylmethyl)bicyclo[2.2.1]hepta-2,5-diene giving (S)-di-tert-Bu phenylbutanedioate (90% yield, 90% ee). The structure of [RhCl(1)]₂ (1 = (1R,4R)-2,5-di(phenylmethyl)bicyclo[2.2.1]hepta-2,5-diene) was determined by x-ray crystallog. 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: 252288-04-3Recommanded Product: 252288-04-3).

(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. Many phosphine-catalyzed reactions have been developed for the syntheses of various biologically important acyclic and cyclic molecules. Asymmetric variants of these reactions have evolved relatively slowly. Over the last decade, however, and especially since 2005, considerable progress has been made in asymmetric phosphine catalysis.Recommanded Product: 252288-04-3

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Boryl-Dictated Site-Selective Intermolecular Allylic and Propargylic C-H Amination was written by Liu, Yuan;Chen, Zhi-Hao;Li, Yin;Qian, Jiasheng;Li, Qingjiang;Wang, Honggen. And the article was included in Journal of the American Chemical Society in 2022.SDS of cas: 252288-04-3 This article mentions the following:

For internal alkenes possessing two or more sets of electronically and sterically similar allylic protons, the site-selectivity for allylic C-H functionalization is fundamentally challenging. Previously, the neg. inductive effect from an electroneg. atom is effective for several inspiring regioselective C-H functionalization reactions. Yet, the use of an electropos. atom for a similar purpose remains to be developed. α-Aminoboronic acids and their derivatives found widespread applications. Their current syntheses rely heavily on functional group manipulations. Herein the authors report a boryl-directed intermol. C-H amination of allyl N-methyliminodiacetyl boronates (B(MIDA)s) and propargylic B(MIDA)s to give α-amino boronates with an exceptionally high level of site-selectivities (up to 300:1). A wide variety of highly functionalized secondary and tertiary α-amino boronates are formed in generally good to excellent yields, thanks to the mildness of the reaction conditions. The unsaturated double and triple bonds within the product leave room for further decorations. Mechanistic studies reveal that the key stabilization effect of the B(MIDA) moiety on its adjacent developing pos. charge is responsible for the high site-selectivity and that a closed transition state might be involved, as the reaction is fully stereoretentive. An activation effect of B(MIDA) is also found. 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: 252288-04-3SDS of cas: 252288-04-3).

(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. Effective chiral catalysts for nucleophilic phosphine catalysis are scarce, seriously limiting the development of asymmetric variants. SDS of cas: 252288-04-3

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis