chiral-phosphine-ligands| Page 24 of 630 | Chiral phosphine ligands

Kang, Qiang et al. published their research in Advanced Synthesis & Catalysis in 2007 | CAS: 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. Thousands of arylphosphines have been used as chiral ligands for metal-catalyzed asymmetric reactions. 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

Highly enantioselective transfer hydrogenation of α-imino esters by a phosphoric acid was written by Kang, Qiang;Zhao, Zhuo-An;You, Shu-Li. And the article was included in Advanced Synthesis & Catalysis in 2007.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 acids have been identified as highly efficient organocatalysts for the asym. transfer hydrogenation of α-imino esters and amide. Utilizing Hantzsch esters as the hydrogen donor, versatile highly enantioenriched α-amino esters and their derivatives were obtained with up to 98% 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).

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Lorraine, Shannen’s team published research in Inorganica Chimica Acta in 511 | CAS: 1365531-76-5

Inorganica Chimica Acta published new progress about 1365531-76-5. 1365531-76-5 belongs to chiral-phosphine-ligands, auxiliary class (Atropisomeric Bisphosphine Ligands, name is (S)-2,2′-Bis(diphenylphosphino)-4,4′,6,6′-tetramethoxy)-1,1′-biphenyl, and the molecular formula is C40H36O4P2, Quality Control of 1365531-76-5.

Lorraine, Shannen published the artcileBiaryl diphosphine ligands and their ruthenium complexes: Preparation and use for catalytic hydrogenation of ketones, Quality Control of 1365531-76-5, the publication is Inorganica Chimica Acta (2020), 119850, database is CAplus.

Procedures for the preparation of the nucleophilic diphosphine ligands (R)-(4,4′,6,6′-tetramethoxybiphenyl-2,2′-diyl)bis(diphenylphosphine) ((R)-Ph-Garphos) and (S)-(4,4′,6,6′-tetramethoxybiphenyl-2,2′-diyl)bis(diphenylphosphine) ((S)-Ph-Garphos) were described. The ligands were used to prepare the ruthenium(II) Ph-Garphos complexes, chloro(p-cymene)(R)-(4,4′,6,6′-tetraamethoxybiphenyl-2,2′-diyl)bis(diphenylphosphine)ruthenium(II) chloride ([RuCl(p-cymene)(R)-Ph-Garphos]Cl (3)) and chloro(p-cymene)(S)-(4,4′,6,6′-tetraamethoxybiphenyl-2,2′-diyl)bis(diphenylphosphine)ruthenium(II) chloride ([RuCl(p-cymene)(S)-Ph-Garphos]Cl (4)). In the presence of the chiral diamine co-ligands (1R,2R)-1,2-diphenylethane-1,2-diamine (R,R-DPEN) and (1S,2S)-1,2-diphenylethane-1,2-diamine (S,S-DPEN), complexes 3 and 4 were found to be catalyst precursors for the enantioselective reduction of aryl ketones under mild conditions (room temperature and 3-4 atm of H₂). The chiral alcs. were isolated in moderate to good yields and with enantioselectivities of up to 93%. The ruthenium complexes chloro(p-cymene)(R)-(4,4′,6,6′-tetramethoxybiphenyl-2,2′-diyl)bis(bis(3,5-dimethylphenyl)-phosphine)ruthenium(II) chloride ([RuCl(p-cymene)(R)-Xyl-Garphos]Cl (5)) and chloro(p-cymene)(S)-(4,4′,6,6′-tetramethoxybiphenyl-2,2′-diyl)bis(bis(3,5-dimethylphenyl)-phosphine)ruthenium(II) chloride ([RuCl(p-cymene)(S)-Xyl-Garphos]Cl (6)) were also prepared and used as catalyst precursors for the hydrogenation of aryl ketones in the presence of (R,R)-DPEN and (S,S)-DPEN. Significant improvements in the enantioselectivities of the alcs. (up to 98% ee.) were afforded. A combination of 6 and (S,S)-DPEN afforded (R)-1-(3-methoxyphenyl)ethanol in 89% yield and with 95% ee which was shown to be a suitable precursor for the preparation of (S)-rivastigmine.

Referemce:
https://en.wikipedia.org/wiki/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

Pan, Subhas Chandra’s team published research in Angewandte Chemie, International Edition in 46 | CAS: 929294-27-9

Angewandte Chemie, International Edition published new progress about 929294-27-9. 929294-27-9 belongs to chiral-phosphine-ligands, auxiliary class Chiral Phosphoric Acids, name is R-3,3′-Bis(2,4,6-triisopropylphenyl)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl-2,2′-diyl hydrogenphosphate, and the molecular formula is C50H65O4P, Safety of R-3,3′-Bis(2,4,6-triisopropylphenyl)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl-2,2′-diyl hydrogenphosphate.

Pan, Subhas Chandra published the artcileCatalytic asymmetric acylcyanation of imines. [Erratum to document cited in CA146:337461], Safety of R-3,3′-Bis(2,4,6-triisopropylphenyl)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl-2,2′-diyl hydrogenphosphate, the publication is Angewandte Chemie, International Edition (2007), 46(17), 2971, database is CAplus.

On page 614, reference [11c], citation of a parallel report discussing a non-enantioselective variant of the presented reaction was omitted. Reference [11c] should read: “c) for a non-enantioselective thiourea-catalyzed variant, see: S. C. Pan, J. Zhou, B. List, Synlett 2006, 3275-3276.”.

Avila, Carolina M.’s team published research in Angewandte Chemie, International Edition in 56 | CAS: 929294-27-9

Angewandte Chemie, International Edition published new progress about 929294-27-9. 929294-27-9 belongs to chiral-phosphine-ligands, auxiliary class Chiral Phosphoric Acids, name is R-3,3′-Bis(2,4,6-triisopropylphenyl)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl-2,2′-diyl hydrogenphosphate, and the molecular formula is C50H65O4P, Application of R-3,3′-Bis(2,4,6-triisopropylphenyl)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl-2,2′-diyl hydrogenphosphate.

Avila, Carolina M. published the artcileEnantioselective Heck-Matsuda Arylations through Chiral Anion Phase-Transfer of Aryl Diazonium Salts, Application of R-3,3′-Bis(2,4,6-triisopropylphenyl)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl-2,2′-diyl hydrogenphosphate, the publication is Angewandte Chemie, International Edition (2017), 56(21), 5806-5811, database is CAplus and MEDLINE.

A mild, asym. Heck-Matsuda reaction of five-, six- and seven-membered ring alkenes and aryl diazonium salts is presented. High yields and enantioselectivities were achieved using Pd⁰ and chiral anion co-catalysts, the latter functioning as a chiral anion phase-transfer (CAPT) reagent. For certain substrate classes, the chiral anion catalysts were modulated to minimize the formation of undesired byproducts. More specifically, BINAM-derived phosphoric acid catalysts were shown to prevent alkene isomerization in cyclopentene and cycloheptene starting materials. DFT(B3LYP-D3) computations revealed that increased product selectivity resulted from a chiral anion dependent lowering of the activation barrier for the desired pathway.

Angewandte Chemie, International Edition published new progress about 929294-27-9. 929294-27-9 belongs to chiral-phosphine-ligands, auxiliary class Chiral Phosphoric Acids, name is R-3,3′-Bis(2,4,6-triisopropylphenyl)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl-2,2′-diyl hydrogenphosphate, and the molecular formula is C50H65O4P, Application of R-3,3′-Bis(2,4,6-triisopropylphenyl)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl-2,2′-diyl hydrogenphosphate.

Alvim, Haline G. O.’s team published research in Journal of Organic Chemistry in 83 | CAS: 929294-27-9

Journal of Organic Chemistry published new progress about 929294-27-9. 929294-27-9 belongs to chiral-phosphine-ligands, auxiliary class Chiral Phosphoric Acids, name is R-3,3′-Bis(2,4,6-triisopropylphenyl)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl-2,2′-diyl hydrogenphosphate, and the molecular formula is C50H65O4P, Safety of R-3,3′-Bis(2,4,6-triisopropylphenyl)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl-2,2′-diyl hydrogenphosphate.

Alvim, Haline G. O. published the artcileCombined Role of the Asymmetric Counteranion-Directed Catalysis (ACDC) and Ionic Liquid Effect for the Enantioselective Biginelli Multicomponent Reaction, Safety of R-3,3′-Bis(2,4,6-triisopropylphenyl)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl-2,2′-diyl hydrogenphosphate, the publication is Journal of Organic Chemistry (2018), 83(19), 12143-12153, database is CAplus and MEDLINE.

This work describes new chiral task-specific ionic liquids bearing chiral anions as the catalysts for the enantioselective multicomponent Biginelli reaction. For the first time, the combined role of asym. counteranion-directed catalysis (ACDC) and ionic liquid effect (ILE) for the chiral induction in the Biginelli multicomponent reaction is demonstrated. The chiral induction arises from a supramol. aggregate where the anion and the cation of the catalyst are alongside with a key cationic intermediate of the reaction. Each component of the new catalyst had a vital role for the chiral induction success. The mechanism of an asym. version of this multicomponent reaction is in addition demonstrated for the first time using electrospray (tandem) mass spectrometry, ESI-MS(/MS). The analyses indicated the reaction takes place preferentially and exclusively through the iminium mechanism. Unprecedented supramol. aggregates were detected by ESI-MS and characterized by ESI-MS/MS. No intermediate of the other two possible reactions pathways could be detected. Theor. calculations shed light on the transition state of the transformation during the key step of the chiral induction and helped to elucidate the roles of the chiral anion (ACDC contribution) and of the imidazolium-containing nonchiral cation derivative (ILE contribution) in the mol. reaction process.

Romanov-Michailidis, Fedor’s team published research in Chemical Communications (Cambridge, United Kingdom) in 50 | CAS: 929294-27-9

Chemical Communications (Cambridge, United Kingdom) published new progress about 929294-27-9. 929294-27-9 belongs to chiral-phosphine-ligands, auxiliary class Chiral Phosphoric Acids, name is R-3,3′-Bis(2,4,6-triisopropylphenyl)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl-2,2′-diyl hydrogenphosphate, and the molecular formula is C50H65O4P, Safety of R-3,3′-Bis(2,4,6-triisopropylphenyl)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl-2,2′-diyl hydrogenphosphate.

Romanov-Michailidis, Fedor published the artcileEnantioselective halogenative semi-pinacol rearrangement: a stereodivergent reaction on a racemic mixture, Safety of R-3,3′-Bis(2,4,6-triisopropylphenyl)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl-2,2′-diyl hydrogenphosphate, the publication is Chemical Communications (Cambridge, United Kingdom) (2014), 50(88), 13461-13464, database is CAplus and MEDLINE.

An efficient, quant. deracemization strategy for optically inactive allylic cycloalkanols, e.g. I, has been achieved using the biphasic halogenative semi-pinacol reaction protocol. The resultant β-halo spiroketones, containing three contiguous stereogenic centers, e.g. II, were easily recovered with high diastereomeric and enantiomeric purities following conventional silica gel chromatog. The optically active products could be further manipulated chem., affording synthetically interesting scaffolds with complete preservation of stereoisomeric integrity.

Romanov-Michailidis, Fedor’s team published research in Organic Letters in 16 | CAS: 929294-27-9

Organic Letters published new progress about 929294-27-9. 929294-27-9 belongs to chiral-phosphine-ligands, auxiliary class Chiral Phosphoric Acids, name is R-3,3′-Bis(2,4,6-triisopropylphenyl)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl-2,2′-diyl hydrogenphosphate, and the molecular formula is C50H65O4P, Recommanded Product: R-3,3′-Bis(2,4,6-triisopropylphenyl)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl-2,2′-diyl hydrogenphosphate.

Romanov-Michailidis, Fedor published the artcileEnantioselective Catalytic Fluorinative Aza-semipinacol Rearrangement, Recommanded Product: R-3,3′-Bis(2,4,6-triisopropylphenyl)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl-2,2′-diyl hydrogenphosphate, the publication is Organic Letters (2014), 16(19), 4988-4991, database is CAplus and MEDLINE.

An efficient and highly stereoselective fluorinative aza-semipinacol rearrangement is described. The catalytic reaction requires use of Selectfluor in combination with the chiral, enantiopure phosphate anion derived from acid. Under optimized conditions, cyclopropylamines were transformed into β-fluoro cyclobutylimines in good yields and high levels of diastereo- and enantiocontrol. Furthermore, the optically active cyclobutylimines were reduced diastereoselectively with L-Selectride in the corresponding fluorinated amines, compounds of significant interest in the pharmacol. industry.

Gao, Zeng’s team published research in Chemical Communications (Cambridge, United Kingdom) in 56 | CAS: 929294-27-9

Gao, Zeng published the artcileChiral Bronsted acid-catalyzed dynamic kinetic resolution of atropisomeric ortho-formyl naphthamides, Product Details of C50H65O4P, the publication is Chemical Communications (Cambridge, United Kingdom) (2020), 56(53), 7265-7268, database is CAplus and MEDLINE.

Despite the widespread use of naphthamide atropisomers in biol. active compounds and asym. catalysis, few catalytic methods have succeeded in the enantioselective synthesis of these compounds Herein, a chiral Bronsted acid (CBA) catalysis strategy was developed for readily scalable dynamic kinetic resolution of challenging ortho-formyl naphthamides with pyrrolylanilines. The chiral axis of the atropisomeric amide and a stereogenic center were simultaneously established for a new family of potential biol. active pyrrolopyrazine compounds with high enantio- and diastereoselectivities (up to >20 : 1 d.r. and 98 : 2 e.r.). Epimerization experiments of its derivatives reveal that the N-substitution of the nearby stereogenic center could affect the configurational stability of the axially chiral aromatic amides. These results might be useful for the construction of other kinds of novel axially chiral mols. with a low rotational barrier.

Romanov-Michailidis, Fedor’s team published research in Chemistry – A European Journal in 21 | CAS: 929294-27-9

Chemistry – A European Journal published new progress about 929294-27-9. 929294-27-9 belongs to chiral-phosphine-ligands, auxiliary class Chiral Phosphoric Acids, name is R-3,3′-Bis(2,4,6-triisopropylphenyl)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl-2,2′-diyl hydrogenphosphate, and the molecular formula is C50H65O4P, Synthetic Route of 929294-27-9.

Romanov-Michailidis, Fedor published the artcileEnantioselective Halogenative Semi-Pinacol Rearrangement: Extension of Substrate Scope and Mechanistic Investigations, Synthetic Route of 929294-27-9, the publication is Chemistry – A European Journal (2015), 21(14), 5561-5583, database is CAplus and MEDLINE.

The present Full Paper article discloses a survey of our recent results obtained in the context of the enantioselective halogenation-initiated semi-pinacol rearrangement. Commencing with the fluorination/semi-pinacol reaction first and moving to the heavier halogens (bromine and iodine) second, the scope and limitations of the halogenative phase-transfer methodol. will be discussed and compared. An extension of the fluorination/semi-pinacol reaction to the ring-expansion of five-membered allylic cyclopentanols will be also described, as well as some preliminary results on substrates prone to desymmetrization will be given. Finally, the present manuscript will culminate with a detailed mechanistic investigation of the canonical fluorination/semi-pinacol reaction. Our mechanistic discussion will be based on in situ reaction progress monitoring, complemented with substituent effect, kinetic isotopic effect and non-linear behavior studies.

Ray, Sumit K.’s team published research in Organic Letters in 21 | CAS: 929294-27-9

Ray, Sumit K. published the artcileA General Catalytic Route to Enantioenriched Isoindolinones and Phthalides: Application in the Synthesis of (S)-PD 172938, Recommanded Product: R-3,3′-Bis(2,4,6-triisopropylphenyl)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl-2,2′-diyl hydrogenphosphate, the publication is Organic Letters (2019), 21(2), 417-422, database is CAplus and MEDLINE.

Chiral Bronsted acid catalyzed enantioselective syntheses of isoindolinones, e.g. I, and phthalides have been accomplished via tandem Mannich-lactamization and aldol-lactonization reactions, resp. A variety of enantioenriched isoindolinones (up to 99% ee) and phthalides (up to 85% ee) containing α-diazoesters were afforded in excellent yields. Furthermore, a concise synthesis of (S)-PD 172938 has been demonstrated by using this protocol.