Day: February 22, 2023

Half-sandwich rhodium (and iridium) complexes as enantioselective catalysts for the 1,3-dipolar cycloaddition of 3,4-dihydroisoquinoline n-oxide to methacrylonitrile was written by Carmona, Daniel;Lamata, M. Pilar;Viguri, Fernando;Rodriguez, Ricardo;Lahoz, Fernando J.;Oro, Luis A.. And the article was included in Chemistry – A European Journal in 2007.Application of 37002-48-5 This article mentions the following:

Cationic half-sandwich complexes containing the [(η⁵-C₅Me₅)M-(Diphos^*)] moiety (M = Rh, Ir; Diphos^* = chiral diphosphine ligand) catalyze the cycloaddition of the nitrone 3,4-dihydroisoquinoline N-oxide (A) to methacrylonitrile (B) with excellent regio and endo selectivity and low-to-moderate enantioselectivity. The most active and selective catalyst, (S_Rh,R_C)-[(η⁵-C₅Me₅)Rh{(R)-Prophos}(NC(Me)C:CH₂)](SbF₆)₂, has been isolated and fully characterized including the determination of the mol. structure by x-ray diffraction. The R-at-metal epimers of the complexes [(η⁵-C₅Me₅)M{(R)-Prophos}(NC(Me)C:CH₂)](SbF₆)₂ (M = Rh, Ir) isomerize to the corresponding S-at-metal diastereomers. The stoichiometric cycloaddition of A with B is catalyzed by diastereopure (S_M,R_C)-[(η⁵-C₅Me₅)M{(R)-Prophos}(NC(Me)C:CH₂)](SbF₆)₂ with perfect regio and endo selectivity and very good (up to 95%) ee. The catalyst can be recycled up to nine times without significant loss of either activity or selectivity. In the experiment, the researchers used many compounds, for example, (((4S,5S)-2,2-Dimethyl-1,3-dioxolane-4,5-diyl)bis(methylene))bis(diphenylphosphine) (cas: 37002-48-5Application of 37002-48-5).

(((4S,5S)-2,2-Dimethyl-1,3-dioxolane-4,5-diyl)bis(methylene))bis(diphenylphosphine) (cas: 37002-48-5) belongs to chiral phosphine ligands. The synthesis of novel trialkylphosphines can be quite difficult, thereby limiting the scope of their chiral variants. Asymmetric catalytic performance is determined not only by the metal center but also by the chiral ligand selected.Application of 37002-48-5

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Palladium-catalyzed intramolecular direct arylation for phosphorus heterocycle synthesis was written by Chen, Yun-Rong;Duan, Wei-Liang. And the article was included in Synthesis in 2014.Synthetic Route of C33H25OP This article mentions the following:

A Pd-catalyzed intramol. direct arylation of bromo-substituted phosphine oxides is reported for the synthesis of P-containing heterocycles with good to excellent yields (78-98 %). E.g., reaction of Ph₂P(O)CH₂-2-C₆H₄Br with 10 mol% Pd(OAc)₂/10 mol% PPh₃ with K₂CO₃/DMA at 60° gave a 98% yield of 5,6-dihydro-5-phenylphosphanthridine 5-oxide. In the experiment, the researchers used many compounds, for example, (S)-(2′-Methoxy-[1,1′-binaphthalen]-2-yl)diphenylphosphine (cas: 134484-36-9Synthetic Route of C33H25OP).

(S)-(2′-Methoxy-[1,1′-binaphthalen]-2-yl)diphenylphosphine (cas: 134484-36-9) 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.Synthetic Route of C33H25OP

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Regio- and Enantioselective Decarboxylative Allylic Benzylation Enabled by Dual Palladium/Photoredox Catalysis was written by Song, Changhua;Zhang, Hong-Hao;Yu, Shouyun. And the article was included in ACS Catalysis in 2022.Quality Control of (R)-(-)-2,2′-Bis[di(3,5-di-t-butyl-4-methoxyphenyl)phosphino]-6,6′-dimethoxy-1,1′-biphenyl This article mentions the following:

A decarboxylative allylic benzylation cocatalyzed by Pd/photoredox in a regio- and enantioselective manner has been achieved. Readily available aryl acetic acids are used as benzylic nucleophile equivalent without preactivation. This mild and atom economic protocol expands the scope of coupling partners of allylic electrophiles. Vinyl epoxides could also go through this transformation smoothly, affording various chiral homoallylic alcs. bearing all-carbon quaternary stereocenters. In the experiment, the researchers used many compounds, for example, (R)-(-)-2,2′-Bis[di(3,5-di-t-butyl-4-methoxyphenyl)phosphino]-6,6′-dimethoxy-1,1′-biphenyl (cas: 352655-61-9Quality Control of (R)-(-)-2,2′-Bis[di(3,5-di-t-butyl-4-methoxyphenyl)phosphino]-6,6′-dimethoxy-1,1′-biphenyl).

(R)-(-)-2,2′-Bis[di(3,5-di-t-butyl-4-methoxyphenyl)phosphino]-6,6′-dimethoxy-1,1′-biphenyl (cas: 352655-61-9) 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. Trivalent phosphorus compounds called phosphines have a tetrahedral electron-group geometry which makes them structurally analogous to amines.Quality Control of (R)-(-)-2,2′-Bis[di(3,5-di-t-butyl-4-methoxyphenyl)phosphino]-6,6′-dimethoxy-1,1′-biphenyl

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Preparation and evaluation of novel chiral stationary phases based on quinine derivatives comprising crown ether moieties was written by Wang, Dongqiang;Zhao, Jianchao;Wu, Haixia;Wu, Haibo;Cai, Jianfeng;Ke, Yanxiong;Liang, Xinmiao. And the article was included in Journal of Separation Science in 2015.Related Products of 297752-25-1 This article mentions the following:

The C9-position of quinine was modified by meta- or para-substituted benzo-18-crown-6, and immobilized on 3-mercaptopropyl-modified silica gel through the radical thiol-ene addition reaction. These two chiral stationary phases were evaluated by chiral acids, amino acids, and chiral primary amines. The crown ether moiety on the quinine anion exchanger provided a ligand-exchange site for primary amino groups, which played an important role in the retention and enantioselectivity for chiral compounds containing primary amine groups. These two stationary phases showed good selectivity for some amino acids. The complex interaction between crown ether and protonated primary amino group was studied by the addition of inorganic salts such as LiCl, NH₄Cl, NaCl, and KCl to the mobile phase. The resolution results showed that the simultaneous interactions between two function moieties (quinine and crown ether) and amino acids were important for the chiral separation In the experiment, the researchers used many compounds, for example, (R)-4-Hydroxy-8,9,10,11,12,13,14,15-octahydrodinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepine 4-oxide (cas: 297752-25-1Related Products of 297752-25-1).

(R)-4-Hydroxy-8,9,10,11,12,13,14,15-octahydrodinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepine 4-oxide (cas: 297752-25-1) 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.Related Products of 297752-25-1

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Nickel(0)-Catalyzed Asymmetric Ring Expansion Toward Enantioenriched Silicon-Stereogenic Benzosiloles was written by Zhang, Jinyu;Yan, Nuo;Ju, Cheng-Wei;Zhao, Dongbing. And the article was included in Angewandte Chemie, International Edition in 2021.Category: chiral-phosphine-ligands This article mentions the following:

The development of a straightforward strategy to obtain enantioenriched silicon-stereogenic benzosiloles remains a challenging yet appealing synthesis venture due to their potential future application in chiral electronic and optoelectronic devices. In this context, all of the existing methods rely on Rh-catalyzed systems and are somewhat limited in scope. Herein, we disclose the first Ni⁰-catalyzed ring expansion process that enables the preparation of benzosiloles possessing tetraorganosilicon stereocenters in excellent yields and enantioselectivities. The presented catalysis strategy is further applied to the asym. synthesis of silicon-stereogenic bis-silicon-bridged π-extended systems. Preliminary studies reveal that such compounds exhibit fluorescence emission, Cotton effects and circularly polarized luminescence (CPL) activity. In the experiment, the researchers used many compounds, for example, (R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine) (cas: 133545-16-1Category: chiral-phosphine-ligands).

(R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine) (cas: 133545-16-1) 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. Chiral phosphine catalysts: Nucleophilic phosphine catalysis often involves the formation of Lewis adducts, namely phosphonium (di)enolate zwitterions, as reaction intermediates.Category: chiral-phosphine-ligands

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Catalyst-Directed Diastereoselectivity in Hydrogenative Couplings of Acetylene to α-Chiral Aldehydes: Formal Synthesis of All Eight L-Hexoses was written by Han, Soo Bong;Kong, Jong Rock;Krische, Michael J.. And the article was included in Organic Letters in 2008.Formula: C38H32O2P2 This article mentions the following:

Hydrogenative coupling of acetylene to α-chiral aldehydes using enantiomeric rhodium catalysts ligated by (S)-MeO-BIPHEP and (R)-MeO-BIPHEP delivers the diastereomeric products of carbonyl-(Z)-butadienylation with good to excellent levels of catalyst directed diastereofacial selectivity. Diastereomeric L-glyceraldehyde acetonide adducts were converted to the four isomeric enoates, e.g. I, representing a formal synthesis of all eight L-hexoses. In the experiment, the researchers used many compounds, for example, (R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine) (cas: 133545-16-1Formula: C38H32O2P2).

(R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine) (cas: 133545-16-1) 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. Formula: C38H32O2P2

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Reversible nucleophilic addition can lower the observed enantioselectivity in palladium-catalyzed allylic amination reactions with a variety of chiral ligands was written by Caminiti, Nicholas S.;Goodstein, Madison B.;Leibler, Isabelle N.-M.;Holtzman, Bryan S.;Jia, Zitong B.;Martini, Michael L.;Nelson, Nathaniel C.;Bunt, Richard C.. And the article was included in Tetrahedron Letters in 2015.Application of 174810-09-4 This article mentions the following:

Palladium-catalyzed allylic amination is an important synthetic reaction that is also frequently used as a benchmark for the design and evaluation of new chiral ligands. The effect of reversible nucleophilic addition on the reaction of benzylamine with (E)-1,3-diphenylallyl Et carbonate (1) in CH₂Cl₂ was examined with 12 different chiral ligands across a range of scaffolding types. In 8 out of 12 cases the observed ee was significantly higher when DBU or Cs₂CO₃ was added to suppress the proton-driven reversibility. For chiral ligand screening with this test reaction, adding DBU or Cs₂CO₃ provides a better measure of the ligand’s inherent enantioselectivity. In the experiment, the researchers used many compounds, for example, N,N’-((1R,2R)-Cyclohexane-1,2-diyl)bis(2-(diphenylphosphino)-1-naphthamide) (cas: 174810-09-4Application of 174810-09-4).

N,N’-((1R,2R)-Cyclohexane-1,2-diyl)bis(2-(diphenylphosphino)-1-naphthamide) (cas: 174810-09-4) 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.Application of 174810-09-4

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Practical Synthesis of MDM2 Antagonist RG7388. Part 2: Development of the Cu(I) Catalyzed [3 + 2] Asymmetric Cycloaddition Process for the Manufacture of Idasanutlin was written by Rimmler, Gosta;Alker, Andre;Bosco, Marcello;Diodone, Ralph;Fishlock, Dan;Hildbrand, Stefan;Kuhn, Bernd;Moessner, Christian;Peters, Carsten;Rege, Pankaj D.;Schantz, Markus. And the article was included in Organic Process Research & Development in 2016.COA of Formula: C38H32O2P2 This article mentions the following:

A concise catalytic asym. synthesis of idasanutlin was developed in which the key pyrrolidine core, containing four contiguous stereocenters, was constructed via a Ag/MeOBIPHEP promoted [3+2] cycloaddition reaction. Further development of the [3+2] cycloaddition reaction resulted in an improvement in diastereoselectivity and enantioselectivity by changing the catalyst system to Cu(I)/BINAP. While producing equivalent high quality API, the copper(I) catalyzed process not only increased the overall yield but also demonstrated benefit with respect to cycle times, waste streams and processability. The optimized copper(I) catalyzed process has been used to prepare more than 1500 kg of idasanutlin. In the experiment, the researchers used many compounds, for example, (R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine) (cas: 133545-16-1COA of Formula: C38H32O2P2).

(R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine) (cas: 133545-16-1) belongs to chiral phosphine ligands. The synthesis of novel trialkylphosphines can be quite difficult, thereby limiting the scope of their chiral variants. Asymmetric catalytic performance is determined not only by the metal center but also by the chiral ligand selected.COA of Formula: C38H32O2P2

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Enantioselective vinylation of aldehydes with chiral β-silylphosphorus ylides was written by Iio, Hideo;Fujii, Akio;Ishii, Masahiro;Tokoroyama, Takashi. And the article was included in Journal of the Chemical Society, Chemical Communications in 1991.Name: (R)-N,N-Dimethyl-1-[(R)-2-(diphenylphosphino)ferrocenyl]ethylamine This article mentions the following:

Both enantiomers of diastereoisomeric [1-(dimethylaminoethyl)ferrocenyl]diphenyl(2-diphenylmethylsilylethylidene)phosphorane are prepared; their reaction with benzaldehyde and aliphatic aldehydes is found to give vinylation products with variable enantiomeric excess (up to 92%). In the experiment, the researchers used many compounds, for example, (R)-N,N-Dimethyl-1-[(R)-2-(diphenylphosphino)ferrocenyl]ethylamine (cas: 55700-44-2Name: (R)-N,N-Dimethyl-1-[(R)-2-(diphenylphosphino)ferrocenyl]ethylamine).

(R)-N,N-Dimethyl-1-[(R)-2-(diphenylphosphino)ferrocenyl]ethylamine (cas: 55700-44-2) belongs to chiral phosphine ligands. Thousands of arylphosphines have been used as chiral ligands for metal-catalyzed asymmetric reactions. Effective chiral catalysts for nucleophilic phosphine catalysis are scarce, seriously limiting the development of asymmetric variants. Name: (R)-N,N-Dimethyl-1-[(R)-2-(diphenylphosphino)ferrocenyl]ethylamine

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Synthesis of bornene-2,2′-diamino-1,1′-binaphthalene conjugates in palladium-catalysed aminocarbonylations was written by Mikle, Gabor;Boros, Borbala;Kollar, Laszlo. And the article was included in Tetrahedron: Asymmetry in 2016.Product Details of 77876-39-2 This article mentions the following:

Palladium-catalyzed aminocarbonylation of a terpenoic iodoalkene (2-iodobornene) model compound with both enantiomerically pure and racemic 2,2′-diamino-1,1′-binaphthalene (BINAM) as the N-nucleophile was carried out. All of the diastereoisomers of the monocarboxamide (N-bornenyl carboxamide) and dicarboxamide (N,N’-dinorbornenylcarboxamide) derivatives were synthesized. The diastereoselectivities of the aminocarbonylation were investigated in both cases: either racemic BINAM was used as the N-nucleophile in the aminocarbonylation of enantiomerically pure 2-iodobornene or racemic iodobornene was aminocarbonylated with enantiomerically pure BINAM with moderate diastereoselectivities. In this way, all possible diastereoisomers of binaphthalene-bornene conjugates were synthesized in moderate to high yields by asym. (diastereoselective) aminocarbonylation. In the experiment, the researchers used many compounds, for example, (2S,4S)-Pentane-2,4-diylbis(diphenylphosphine) (cas: 77876-39-2Product Details of 77876-39-2).

(2S,4S)-Pentane-2,4-diylbis(diphenylphosphine) (cas: 77876-39-2) 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.Product Details of 77876-39-2

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis