Month: October 2022

In 2018,Trost, Barry M.; Bai, Wen-Ju; Stivala, Craig E.; Hohn, Christoph; Poock, Caroline; Heinrich, Marc; Xu, Shiyan; Rey, Jullien published 《Enantioselective Synthesis of des-Epoxy-Amphidinolide N》.Journal of the American Chemical Society published the findings.Synthetic Route of C38H28O4P2 The information in the text is summarized as follows:

The synthesis of des-epoxy-amphidinolide N (I) was achieved in 22 longest linear and 33 total steps. Three generations of synthetic endeavors are reported herein. During the first generation, our key stitching strategy that highlighted an intramol. Ru-catalyzed alkene-alkyne (Ru AA) coupling and a late-stage epoxidation proved successful, but the installation of the α,α’-dihydroxyl ketone motif employing a dihydroxylation method was problematic. Our second generation of synthetic efforts addressed the scalability problem of the southern fragment synthesis and significantly improved the efficiency of the atom-economical Ru AA coupling, but suffered from several protecting group-based issues that proved insurmountable. Finally, relying on a judicious protecting group strategy together with concise fragment preparation, des-epoxy-amphidinolide N was achieved in a convergent fashion. Calculations disclose a hydrogen-bonding bridge within amphidinolide N. Comparisons of 13C NMR chem. shift differences using our synthetic des-epoxy-amphidinolide N suggest that amphidinolide N and carbenolide I are probably identical. In addition to this study using (S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole, there are many other studies that have used (S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole(cas: 210169-54-3Synthetic Route of C38H28O4P2) was used in this study.

(S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole(cas: 210169-54-3) is a chelating ligand used to prepare coordination complex catalysts, such as its use in Pd catalysts for the enantioselective synthesis of spiro- or benzofused hetereocycles with exocyclic olefins via enantioselective intramolecular dearomative Heck reaction of indoles, benzofurans, pyrroles and furans.Synthetic Route of C38H28O4P2

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Zhang, Jiacheng; Huo, Xiaohong; Xiao, Junzhe; Zhao, Ling; Ma, Shengming; Zhang, Wanbin published their research in Journal of the American Chemical Society in 2021. The article was titled 《Enantio- and Diastereodivergent Construction of 1,3-Nonadjacent Stereocenters Bearing Axial and Central Chirality through Synergistic Pd/Cu Catalysis》.Computed Properties of C38H28O4P2 The article contains the following contents:

Herein, an enantio- and diastereodivergent construction of 1,3-nonadjacent stereocenters bearing allenyl axial and central chirality through synergistic Pd/Cu-catalyzed dynamic kinetic asym. allenylation with racemic allenylic esters was reported. The protocol was suitable for a wide range of substrates including the challenging allenylic esters with less sterically bulky substituents and provided chiral allenylic products I [R = n-Bu, Ph, CMe2OTBS, etc.; Ar = Ph, 2-naphthyl, 2-furyl, etc.; stereo = R or S] bearing 1,3-nonadjacent stereocenters with high levels of enantio- and diastereoselectivities (up to >20:1 dr and >99% ee). Furthermore, several representative transformations involving axial-to-central chirality transfer were conducted, affording useful structural motifs containing nonadjacent stereocenters in a diastereodivergent manner. In the experiment, the researchers used (S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole(cas: 210169-54-3Computed Properties of C38H28O4P2)

(S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole(cas: 210169-54-3) is a chelating ligand used to prepare coordination complex catalysts, such as its use in Pd catalysts for the enantioselective synthesis of spiro- or benzofused hetereocycles with exocyclic olefins via enantioselective intramolecular dearomative Heck reaction of indoles, benzofurans, pyrroles and furans.Computed Properties of C38H28O4P2

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Bernardo, Olaya; Gonzalez-Pelayo, Silvia; Fernandez, Israel; Lopez, Luis A. published an article in 2021. The article was titled 《Gold-Catalyzed Reaction of Propargyl Esters and Alkynylsilanes: Synthesis of Vinylallene Derivatives through a Twofold 1,2-Rearrangement》, and you may find the article in Angewandte Chemie, International Edition.Category: chiral-phosphine-ligands The information in the text is summarized as follows:

The reaction of propargyl esters with alkynylsilanes under gold catalysis provides vinylallene derivatives through consecutive [1,2]-acyloxy/[1,2]-silyl rearrangements. Good yields, full atom-economy, broad substrate scope, easy scale-up and low catalyst loadings are salient features of this novel transformation. D. Functional Theory (DFT) calculations suggest a reaction mechanism involving initial [1,2]-acyloxy rearrangement to generate a gold vinylcarbene intermediate which upon regioselective attack of the alkynylsilane affords a vinyl cation which undergoes a type II-dyotropic rearrangement involving the silyl group and the metal fragment. Preliminary results on the enantioselective version of this transformation are also disclosed. The results came from multiple reactions, including the reaction of (S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole(cas: 210169-54-3Category: chiral-phosphine-ligands)

(S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole(cas: 210169-54-3) is a chelating ligand used to prepare coordination complex catalysts, such as its use in Pd catalysts for the enantioselective synthesis of spiro- or benzofused hetereocycles with exocyclic olefins via enantioselective intramolecular dearomative Heck reaction of indoles, benzofurans, pyrroles and furans.Category: chiral-phosphine-ligands

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

In 2022,Zhu, Jian-Xiang; Chen, Zhi-Chao; Du, Wei; Chen, Ying-Chun published an article in Angewandte Chemie, International Edition. The title of the article was 《Asymmetric Auto-Tandem Palladium Catalysis for 2,4-Dienyl Carbonates: Ligand-Controlled Divergent Synthesis》.COA of Formula: C38H28O4P2 The author mentioned the following in the article:

Herein a palladium-catalyzed auto-tandem reaction between 2,4-dienyl carbonates and o-TsNH arylimines or trifluoroacetophenones was presented, that proceeded through a consecutive N-allylation, vinylogous addition, π-σ-π isomerization, and another N-allylation sequence. Importantly, switchable diastereodivergent synthesis could be achieved by tuning the chiral bisphosphine ligands, which led to the construction of a broad spectrum of fused tetrahydroquinoline architectures such as I [R1 = H, 4-Me, 5-Cl, etc.; R2 = Ms, Ts, SO2(2-thienyl); R3 = Me, Ph, 2-furyl, etc.] with moderate to excellent enantioselectivity. Ligand control even enabled effective access to regiodivergent azetidines or chemodivergent β-H elimination with fair enantioselectivity, further showing the versatility of the current auto-tandem catalysis.(S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole(cas: 210169-54-3COA of Formula: C38H28O4P2) was used in this study.

(S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole(cas: 210169-54-3) may be used for: regio- and stereoselective preparation of axially chiral arylnaphthalene derivatives via rhodium-catalyzed [2+2+2] cycloaddition of diynes with naphthalenepropynoic acid derivatives or diastereo- and enantioselective hydrogenation of α-amino-β-keto ester hydrochlorides catalyzed by an iridium complex.COA of Formula: C38H28O4P2

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Application In Synthesis of (S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxoleIn 2021 ,《Computational and Experimental Insights into Asymmetric Rh-Catalyzed Hydrocarboxylation with CO2》 was published in European Journal of Organic Chemistry. The article was written by Pavlovic, Ljiljana; Pettersen, Martin; Gevorgyan, Ashot; Vaitla, Janakiram; Bayer, Annette; Hopmann, Kathrin H.. The article contains the following contents:

The asym. Rh-catalyzed hydrocarboxylation of α,β-unsaturated carbonyl compounds was originally developed by Mikami and co-workers but gives only moderate enantiomeric excesses. In order to understand the factors controlling the enantioselectivity and to propose novel ligands for this reaction, we have used computational and exptl. methods to study the Rh-catalyzed hydrocarboxylation with different bidentate ligands. The anal. of the C-CO2 bond formation transition states with DFT methods shows a preference for outer-sphere CO2 insertion, where CO2 can undergo a backside or frontside reaction with the nucleophile. The two ligands that prefer a frontside reaction, StackPhos and tBu-BOX, display an intriguing stacking interaction between CO2 and an N-heterocyclic ring of the ligand (imidazole or oxazoline). Our exptl. results support the computationally predicted low enantiomeric excesses and highlight the difficulty in developing a highly selective version of this reaction. The experimental part of the paper was very detailed, including the reaction process of (S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole(cas: 210169-54-3Application In Synthesis of (S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole)

(S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole(cas: 210169-54-3) is a chelating ligand used to prepare coordination complex catalysts, such as its use in Pd catalysts for the enantioselective synthesis of spiro- or benzofused hetereocycles with exocyclic olefins via enantioselective intramolecular dearomative Heck reaction of indoles, benzofurans, pyrroles and furans.Application In Synthesis of (S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

《Enantioselective Synthesis of Planar Chiral Zigzag-Type Cyclophenylene Belts by Rhodium-Catalyzed Alkyne Cyclotrimerization》 was written by Nogami, Juntaro; Tanaka, Yusuke; Sugiyama, Haruki; Uekusa, Hidehiro; Muranaka, Atsuya; Uchiyama, Masanobu; Tanaka, Ken. Computed Properties of C38H28O4P2This research focused onzigzag cyclophenylene belt enantioselective preparation; rhodium catalyst enantioselective cyclotrimerization heptynyl oxypropynylphenoxyphenylene oligomer; mol crystal structure racemic zigzag cyclophenylene belt; mechanism enantioselectivity cyclotrimerization heptynyl oxypropynylphenoxyphenylene; ring strain calculated zigzag cyclophenylene belt; fluorescence UV visible absorption zigzag cyclophenylene belt; dissymetry factor ECD CPL nonracemic zigzag cyclophenylene belt. The article conveys some information:

Planar chiral zigzag-type [8] and [12]cyclophenylene belts were prepared enantioselectively by rhodium-catalyzed enantioselective intramol. sequential cyclotrimerizations of a cyclic [oxypropynylbis(heptynyloxy)phenoxybis(heptynyl)phenylene] dimer and trimer. The observed enantioselectivity likely arose from the regioselective formation of a rhodacyclic intermediate from an unsym. triyne unit. The structure of the racemic zigzag [8]cyclophenylene belt was determined by X-ray crystallog.; the homochiral belts mesh with one another to form columns in the solid state, with columns of alternating chiralities. The ring strain of the zigzag [8]cyclophenylene belt was smaller than that of the corresponding armchair-type cycloparaphenylene despite its smaller ring size because of the presence of strain-relieving m-terphenyl moieties. The effect of the number of the benzene rings in the zigzag cyclophenylene belts on their UV/visible absorption and fluorescence was small because of the interruption of conjugation by the m-phenylene moieties, but the effect of bending on the absorption and emission peaks and on the absolute fluorescence quantum yield was significant. Modest anisotropy dissymmetry factors of the electronic CD and CPL spectra were observed for the zigzag [8]cyclophenylene belt. The results came from multiple reactions, including the reaction of (S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole(cas: 210169-54-3Computed Properties of C38H28O4P2)

(S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole(cas: 210169-54-3) may be used for: regio- and stereoselective preparation of axially chiral arylnaphthalene derivatives via rhodium-catalyzed [2+2+2] cycloaddition of diynes with naphthalenepropynoic acid derivatives or diastereo- and enantioselective hydrogenation of α-amino-β-keto ester hydrochlorides catalyzed by an iridium complex.Computed Properties of C38H28O4P2

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

In 2010,Angewandte Chemie, International Edition included an article by Landert, Heidi; Spindler, Felix; Wyss, Adrian; Blaser, Hans-Ulrich; Pugin, Benoit; Ribourduoille, Yann; Gschwend, Bjoern; Ramalingam, Balamurugan; Pfaltz, Andreas. Reference of (R)-1-[(R)-1-(Di-tert-butylphosphino)ethyl]-2-[(R)-phenylphosphinoyl]ferrocene. The article was titled 《Chiral Mixed Secondary Phosphine-Oxide-Phosphines: High-Performing and Easily Accessible Ligands for Asymmetric Hydrogenation》. The information in the text is summarized as follows:

Combining secondary phosphine oxides (SPOs) with phosphines leads to highly effective chiral bidentate ligands for transition-metal-based catalysts. The authors present results for selected members of two SPO-P ligand families based on a chiral ferrocenyl backbone (JoSPOphos) and a menthyl substituent (TerSPOphos), resp. JoSPOphos and TerSPOphos are readily accessible from inexpensive starting materials. The steric and electronic properties of these modular ligands can be easily tuned. In the asym. hydrogenation of functionalized alkenes, their rhodium complexes reacted to give enantioselectivities of up to 99% ee and turnover frequencies of up to 20000 h-1. In the part of experimental materials, we found many familiar compounds, such as (R)-1-[(R)-1-(Di-tert-butylphosphino)ethyl]-2-[(R)-phenylphosphinoyl]ferrocene(cas: 1221746-56-0Reference of (R)-1-[(R)-1-(Di-tert-butylphosphino)ethyl]-2-[(R)-phenylphosphinoyl]ferrocene)

(R)-1-[(R)-1-(Di-tert-butylphosphino)ethyl]-2-[(R)-phenylphosphinoyl]ferrocene(cas: 1221746-56-0) belongs to chiral phosphine ligands. Nucleophilic phosphine catalysis often involves the formation of Lewis adducts, namely phosphonium (di)enolate zwitterions, as reaction intermediates. Reference of (R)-1-[(R)-1-(Di-tert-butylphosphino)ethyl]-2-[(R)-phenylphosphinoyl]ferrocene These intermediates are formed through nucleophilic attack of the phosphine catalysts at electron-poor nuclei (normally carbon atoms) and then proceed through several steps to form new chemical bonds.

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Kalkman, Eric D.; Hartwig, John F. published an article in 2021. The article was titled 《Direct Observation of Diastereomeric α-C-Bound Enolates during Enantioselective α-Arylations: Synthesis, Characterization, and Reactivity of Arylpalladium Fluorooxindole Complexes》, and you may find the article in Journal of the American Chemical Society.Reference of (S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole The information in the text is summarized as follows:

The Pd-catalyzed asym. α-arylation of carbonyl compounds is a valuable strategy to form benzylic stereocenters. However, the origin of the stereoselectivity of these reactions is poorly understood, and little is known about the reactivity of the putative diastereomeric arylpalladium enolate intermediates. To this end, the authors report the synthesis and characterization of diphosphine-ligated arylpalladium fluoroenolate complexes, including complexes bearing a metal-bound, stereogenic C and an enantioenriched chiral diphosphine ligand. These complexes reductively eliminate to form chiral α-aryl-α-fluorooxindoles with enantioselectivities and rates that are relevant to those of the catalytic process with SEGPHOS as the ancillary ligand. Kinetic studies showed that the rate of reductive elimination is slightly slower than the rate of epimerization of the intermediate, causing the reductive elimination step to impart the greatest influence on the enantioselectivity. DFT calculations of these processes are consistent with these exptl. rates and suggest that the minor diastereomer forms the major enantiomer of the product. The rates of reductive elimination from complexes containing a variety of electronically varied aryl ligands revealed the unusual trend that complexes bearing more electron-rich aryl ligands react faster than those bearing more electron-poor aryl ligands. Noncovalent Interaction (NCI) and Natural Bond Orbital (NBO) analyses of the transition-state structures for reductive elimination from the SEGPHOS-ligated complexes revealed key donor-acceptor interactions between the Pd center and the fluoroenolate fragment. These interactions stabilize the pathway to the major product enantiomer more strongly than they stabilize that to the minor enantiomer. The results came from multiple reactions, including the reaction of (S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole(cas: 210169-54-3Reference of (S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole)

(S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole(cas: 210169-54-3) may be used for: rhodium-catalyzed asymmetric formal olefination or cycloaddition of 1,3-dicarbonyl compounds with 1,6-diynes or 1,6-enynes, stereoselective preparation of homoallylic alcohols via Ir-catalyzed stereoselective transfer hydrogenative crotylation of an allylic acetate with alcohols or aldehydesReference of (S)-5,5′-Bis(diphenylphosphino)-4,4′-bi-1,3-benzodioxole

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Formula: C50H56O14P2On November 12, 2014 ,《Copper-Catalyzed Diastereo- and Enantioselective Desymmetrization of Cyclopropenes: Synthesis of Cyclopropylboronates》 appeared in Journal of the American Chemical Society. The author of the article were Parra, Alejandro; Amenos, Laura; Guisan-Ceinos, Manuel; Lopez, Aurora; Garcia Ruano, Jose Luis; Tortosa, Mariola. The article conveys some information:

A novel Cu-catalyzed diastereo- and enantioselective desymmetrization of cyclopropenes to afford nonracemic cyclopropylboronates is described. Trapping the cyclopropylcopper intermediate with electrophilic amines allows for the synthesis of cyclopropylaminoboronic esters and demonstrates the potential of the approach for the synthesis of functionalized cyclopropanes. After reading the article, we found that the author used (R)-(6,6′-Dimethoxybiphenyl-2,2′-diyl)bis[bis(3,4,5-trimethoxyphenyl)phosphine](cas: 256390-47-3Formula: C50H56O14P2)

(R)-(6,6′-Dimethoxybiphenyl-2,2′-diyl)bis[bis(3,4,5-trimethoxyphenyl)phosphine](cas: 256390-47-3) belongs to chiral phosphine ligands. Nucleophilic phosphine catalysis often involves the formation of Lewis adducts, namely phosphonium (di)enolate zwitterions, as reaction intermediates. Formula: C50H56O14P2 These intermediates are formed through nucleophilic attack of the phosphine catalysts at electron-poor nuclei (normally carbon atoms) and then proceed through several steps to form new chemical bonds.

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Reference of (R)-1-[(R)-1-(Di-tert-butylphosphino)ethyl]-2-[(R)-phenylphosphinoyl]ferroceneOn November 29, 2013 ,《Cobalt Precursors for High-Throughput Discovery of Base Metal Asymmetric Alkene Hydrogenation Catalysts》 appeared in Science (Washington, DC, United States). The author of the article were Friedfeld, Max R.; Shevlin, Michael; Hoyt, Jordan M.; Krska, Shane W.; Tudge, Matthew T.; Chirik, Paul J.. The article conveys some information:

Asym. hydrogenation of alkenes is one of the most widely used methods for the preparation of single enantiomer compounds, especially in the pharmaceutical and agrochem. industries. For more than four decades, precious metal complexes containing rhodium, iridium, and ruthenium have been predominantly used as catalysts. Here, we report rapid evaluation of libraries of chiral phosphine ligands with a set of simple cobalt precursors. From these studies, base metal precatalysts have been discovered for the hydrogenation of functionalized and unfunctionalized olefins with high enantiomeric excesses, demonstrating the potential utility of more earth-abundant metals in asym. hydrogenation. In the part of experimental materials, we found many familiar compounds, such as (R)-1-[(R)-1-(Di-tert-butylphosphino)ethyl]-2-[(R)-phenylphosphinoyl]ferrocene(cas: 1221746-56-0Reference of (R)-1-[(R)-1-(Di-tert-butylphosphino)ethyl]-2-[(R)-phenylphosphinoyl]ferrocene)

(R)-1-[(R)-1-(Di-tert-butylphosphino)ethyl]-2-[(R)-phenylphosphinoyl]ferrocene(cas: 1221746-56-0) belongs to chiral phosphine ligands. Nucleophilic phosphine catalysis often involves the formation of Lewis adducts, namely phosphonium (di)enolate zwitterions, as reaction intermediates. These intermediates are formed through nucleophilic attack of the phosphine catalysts at electron-poor nuclei (normally carbon atoms) and then proceed through several steps to form new chemical bonds. Reference of (R)-1-[(R)-1-(Di-tert-butylphosphino)ethyl]-2-[(R)-phenylphosphinoyl]ferrocene

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis