Tag: M.W:700-800

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.”.

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.

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

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.

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.

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

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.

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

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.

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.

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

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.

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.

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

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.

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, Product Details of C50H65O4P.

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

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.

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.

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

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.

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.

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

Liang, Kangjiang published the artcileEnantioselective Radical Cyclization of Tryptamines by Visible Light-Excited Nitroxides, Category: chiral-phosphine-ligands, the publication is Journal of Organic Chemistry (2018), 83(18), 10948-10958, database is CAplus and MEDLINE.

Nitroxides can absorb both UV and visible light, and their electron can be excited from the π-bonding orbital to the antibonding π* orbital or the n-bonding orbital to the antibonding π* orbital, resp. Despite the reported UV-induced hydrogen atom transfer (HAT) process, the potential of nitroxides for visible light-excited photosynthesis is underexplored. Here we demonstrate that nitroxide can convert indole to its radical through a visible light-induced HAT process. A chiral phosphoric acid-catalyzed cyclization of the in situ-formed imine radical, followed by trapping by another mol. of nitroxide, provides the product in high yield and enantioselectivity. To highlight the novelty and efficiency of this strategy, an asym. total synthesis of natural product (-)-verrupyrroloindoline was accomplished in 5 steps.

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, Category: chiral-phosphine-ligands.

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

Zhang, Hua published the artcileVisible-Light-Mediated Formal Carbene Insertion Reaction: Enantioselective Synthesis of 1,4-Dicarbonyl Compounds Containing All-Carbon Quaternary Stereocenter, Category: chiral-phosphine-ligands, the publication is ACS Catalysis (2022), 12(9), 5510-5516, database is CAplus.

Authors developed an efficient visible-light-mediated formal carbene insertion reaction of 1,3-diketones with diazoesters for the construction of enantioenriched 1,4-dicarbonyl compounds with a quaternary carbon center. Combining visible light and a Bronsted acid catalyst, chiral 1,4-dicarbonyl compounds were achieved in good yields with high enantioselectivities by a photochem. carbene transfer protocol.

ACS Catalysis 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 C20H21ClN4O4, Category: chiral-phosphine-ligands.

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