Month: February 2023

Chiral paramagnetic closo-ruthenacarboranes via phosphine-diphosphine displacement reaction of “three-bridge” exo-nido-ruthenacarboranes: Molecular Structure of (-)-[closo-3-Cl-3,3-{(Ph₂PCHCH₃)₂CH₂}-3,1,2-RuC₂B₉H₁₁] and its ortho-cycloboronated derivative was written by Cheredilin, Dmitri N.;Kadyrov, Renat;Dolgushin, Fedor M.;Balagurova, Elena V.;Godovikov, Ivan A.;Solodovnikov, Stanislav P.;Chizhevsky, Igor T.. And the article was included in Inorganic Chemistry Communications in 2005.SDS of cas: 77876-39-2 This article mentions the following:

Ruthenacarboranes with chiral non-racemic (2S,4S)-2,4-bis(diphenylphosphino)pentane ligand were prepared by ligand substitution and cage closing of ruthenium nido-carborane complexes. Treatment of [exo-nido-[Cl(Ph₃P)₂Ru]-(μ-H)₃-10-H-7,8-C₂B₉H₈] (1) with the (2S,4S)-(-)-2,4-bis(diphenylphosphino)pentane (3, BDPP) in toluene results in the formation of three novel optically active diphosphine-ruthenium closo complexes, 18e diamagnetic (-)-[closo-3-Cl-3,3-[(S,S)-BDPP]-3-H-3,1,2-RuC₂B₉H₁₁] (4), and 17e paramagnetic (-)-[closo-3-Cl-3,3-[(S,S)-BDPP]-3,1,2-RuC₂B₉H₁₁] (5) along with its ortho-cycloboronated derivative (-)-[closo-3-Cl-3,3-[(S,S)-Ph₂PCH(CH₃)CH₂CH(CH₃)PPh-ortho-C₆H₄]-3,1,2-RuC₂B₉H₁₀] (6). Both odd-electron complexes 5 and 6 were characterized by single-crystal x-ray diffraction anal. In the experiment, the researchers used many compounds, for example, (2S,4S)-Pentane-2,4-diylbis(diphenylphosphine) (cas: 77876-39-2SDS of cas: 77876-39-2).

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

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Asymmetric synthesis catalyzed by chiral ferrocenylphosphine-transition metal complexes. I. Preparation of chiral ferrocenylphosphines was written by Hayashi, Tamio;Mise, Takaya;Fukushima, Motoo;Kagotani, Masahiro;Nagashima, Nobuo;Hamada, Yuji;Matsumoto, Akira;Kawakami, Sota;Konishi, Mitsuo. And the article was included in Bulletin of the Chemical Society of Japan in 1980.Computed Properties of C26H28FeNP This article mentions the following:

As chiral ligands for transition metal complex catalyzed asym. reactions, various kinds of chiral ferrocenylphosphines, which have planar chirality due to 1,2-unsym. substituted ferrocene structure and also have a functional group on the side chain of the ferrocene nucleus, were prepared (S)-N,N-Dimethyl-1-[(R)-2-(diphenylphosphino)ferrocenyl]ethylamine, (S)-N,N-dimethyl-1-[(R)-1′,2-bis(diphenylphosphino)ferrocenyl]ethylamine and their dimethylphosphino derivatives were prepared by lithiation of optically resolved N,N-dimethyl-1-ferrocenylethylamine. The 1-(dimethylamino)ethyl group on the ferrocenylphosphines was converted stereospecifically by nucleophilic substitution reactions into 1-methoxy-, 1-hydroxy-, 1-diphenylphosphino-, and several 1-(dialkylamino)ethyl groups. 1-(Diphenylphosphino)-2-(dimethylaminomethyl)ferrocene was optically resolved via its phosphine sulfide dibenzoyltartaric acid salt. The relationship between CD spectra of the chiral ferrocenylphosphines and the configuration of their chirality is discussed. In the experiment, the researchers used many compounds, for example, (R)-N,N-Dimethyl-1-[(R)-2-(diphenylphosphino)ferrocenyl]ethylamine (cas: 55700-44-2Computed Properties of C26H28FeNP).

(R)-N,N-Dimethyl-1-[(R)-2-(diphenylphosphino)ferrocenyl]ethylamine (cas: 55700-44-2) belongs to chiral phosphine ligands. The synthesis of novel trialkylphosphines can be quite difficult, thereby limiting the scope of their chiral variants. Trivalent phosphorus compounds called phosphines have a tetrahedral electron-group geometry which makes them structurally analogous to amines.Computed Properties of C26H28FeNP

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Asymmetric Hydrogenation of α-Purine Nucleobase-Substituted Acrylates with Rhodium Diphosphine Complexes: Access to Tenofovir Analogues was written by Sun, Huan-Li;Chen, Fei;Xie, Ming-Sheng;Guo, Hai-Ming;Qu, Gui-Rong;He, Yan-Mei;Fan, Qing-Hua. And the article was included in Organic Letters in 2016.Application In Synthesis of (R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine) This article mentions the following:

The first asym. hydrogenation of α-purine nucleobase-substituted α,β-unsaturated esters, catalyzed by a chiral rhodium (R)-Synphos catalyst, has been developed. A wide range of mono- and disubstituted acrylates were successfully hydrogenated under very mild conditions in high yields with good to excellent enantioselectivities (up to 99% ee). This method provides a convenient approach to the synthesis of a new kind of optically pure acyclic nucleoside and Tenofovir analogs. In the experiment, the researchers used many compounds, for example, (R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine) (cas: 133545-16-1Application In Synthesis of (R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine)).

(R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine) (cas: 133545-16-1) 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.Application In Synthesis of (R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine)

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Supercritical fluid chromatography comparison of the poly(trans-1,2-cyclohexanediyl-bis acrylamide) (P-CAP) column with several derivatized polysaccharide-based stationary phases was written by Barnhart, Wesley W.;Gahm, Kyung H.;Hua, Zheng;Goetzinger, Wolfgang. And the article was included in Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences in 2008.SDS of cas: 37002-48-5 This article mentions the following:

The poly(trans-1,2-cyclohexanediyl-bisacrylamide) (P-CAP) column has so far been primarily used with normal phase and polar organic mobile phase chromatog. Its use in supercritical fluid chromatog. (SFC) was studied via the anal. of 40 com. and 100 proprietary compounds using a 12-min gradient with methanol as a modifier. Results were then compared against those obtained from the popular derivatized polysaccharide-based chiral stationary phases (CSPs) such as Chiralpak AD-H and Chiralpak AS-H as well as Chiralcel OD-H and Chiralcel OJ-H columns. P-CAP demonstrated separation of 25% of the 140 total compounds, while each of the derivatized polysaccharide-based CSPs separated at least 46%. A study that compared the loading of 1,1′-bi-2-naphthol with P-CAP and Chiralpak AS columns indicated a similar trend in resolution vs. amount injected, though AS appeared capable of allowing a greater loading of material. The P-CAP column is beneficial in the separation of a complex mixture of enantiomers and achiral impurities, where the derivatized polysaccharide-based columns did not show as desirable of a separation A key advantage of this type of chiral stationary phase is the fact that it is available in both enantiomeric forms, allowing manipulation of elution order of enantiomers, which is especially helpful for preparative applications. P-CAP also demonstrated that it could resolve an achiral impurity from the desired compound in a different mixture, while the same impurity coeluted on the Chiralpak AD-H column. Overall, the synthetic polymer-based P-CAP showed less chiral discrimination power compared to the derivatized polysaccharide-based CSPs under the conditions explored. 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: 37002-48-5SDS of cas: 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. Thousands of arylphosphines have been used as chiral ligands for metal-catalyzed asymmetric reactions. Most of these phosphines are acyclic, usually possess low nucleophilic activity, and generally display poor enantioselectivities for phosphine organocatalysis. SDS of cas: 37002-48-5

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Enantio- and Diastereoselective Synthesis of Functionalized Carbocycles by Cu-Catalyzed Borylative Cyclization of Alkynes with Ketones was written by Zanghi, Joseph M.;Liu, Shuang;Meek, Simon J.. And the article was included in Organic Letters in 2019.SDS of cas: 133545-16-1 This article mentions the following:

A single-pot Cu-catalyzed enantio- and diastereoselective tandem hydroboration/borylative cyclization of alkynes with ketones for the synthesis of carbocycles is reported. The reaction proceeds via desymmetrization and generates four contiguous stereocenters, including an all-C quaternary center. The method provides rapid access to [6,5]- and [5,5]-bicycles and cyclopentane products. Catalyst-controlled diastereoselectivity by selection of bisphosphine ligand is noted. Utility of the products is demonstrated by site- and chemoselective transformations that afford valuable alkenyl and allyl organoborons. In the experiment, the researchers used many compounds, for example, (R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine) (cas: 133545-16-1SDS of cas: 133545-16-1).

(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. Chiral ligands coordinate to metal centers to create an asymmetric environment around the reaction centers, which eventually affects enantioselectivity and reaction rate.SDS of cas: 133545-16-1

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Synthesis of benzannulated spiroacetals using chiral gold-phosphine complexes and chiral anions was written by Quach, Rachelle;Furkert, Daniel P.;Brimble, Margaret A.. And the article was included in Tetrahedron Letters in 2013.Quality Control of (R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine) This article mentions the following:

The development of an asym. gold-catalyzed dihydroalkoxylation strategy for the synthesis of the 3’H-spiro[chroman-2,1′-isobenzofuran] spiroketal ring system I is described. Spiroacetal I was generated in up to 87:13 enantiomeric ratio using chiral gold-phosphine complexes and chiral silver phosphate Ag(S)-TRIP. In the experiment, the researchers used many compounds, for example, (R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine) (cas: 133545-16-1Quality Control of (R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine)).

(R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine) (cas: 133545-16-1) belongs to chiral phosphine ligands. Although many reactions require more nucleophilic trialkylphosphines as catalysts, only a few chiral trialkylphosphines are available. Effective chiral catalysts for nucleophilic phosphine catalysis are scarce, seriously limiting the development of asymmetric variants. Quality Control of (R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine)

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Improvement of chiral stationary phases based on cinchona alkaloids bonded to crown ethers by chiral modification was written by Zhao, Jianchao;Wu, Haixia;Wang, Dongqiang;Wu, Haibo;Cheng, Lingping;Jin, Yu;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:

To improve the chiral recognition capability of a cinchona alkaloid crown ether chiral stationary phase, the crown ether moiety was modified by the chiral group of (1S,2S)-2-aminocyclohexyl phenylcarbamate. Both quinine and quinidine-based stationary phases were evaluated by chiral acids, chiral primary amines and amino acids. The quinine/quinidine and crown ether provided ion-exchange sites and complex interaction site for carboxyl group and primary amine group in amino acids, resp., which were necessary for the chiral discrimination of amino acid enantiomers. The introduction of the chiral group greatly improved the chiral recognition for chiral primary amines. The structure of crown ether moiety was proved to play a dominant role in the chiral recognitions for chiral primary amines and amino acids. 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. 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.Related Products of 297752-25-1

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Regio- and Stereoselective Synthesis of Key 1-Methyl Carbapenem Intermediates via Hydroformylation Using a Zwitterionic Rhodium Catalyst was written by Park, H. S.;Alberico, E.;Alper, H.. And the article was included in Journal of the American Chemical Society in 1999.Safety of (2S,4S)-Pentane-2,4-diylbis(diphenylphosphine) This article mentions the following:

The asym. hydroformylation of a 4-vinyl β-lactam catalyzed by a rhodium catalyst with a chiral phosphine ligand was investigated. The catalytic system consisting of a zwitterionic rhodium catalyst, (NBD)Rh⁺(C₆H₅B^–Ph₃), and (S,S)-2,4 bis(diphenylphosphino)pentane, (S,S)-BDPP, gave branched aldehydes in high regio- and stereoselectivity. The hydroformylated products are key intermediates in the synthesis of 1-methylcarbapenem antibiotics. Using (3S,4R)-3-[(R)-1-(tert-butyldimethyl-silyloxy)ethyl]-4-vinyl-2-azetidinone as the reactant afforded aldehydes in a 97:3 branched-to-linear ratio and 91:9 to β- to α-branched isomers. The regio (branched/linear)- and stereoselectivity (β/α) was >99:1 when (3S,4R)-1-N-BOC-3-[(R)-1-methoxyethyl]-4-vinyl-2-azetidinone was used as the substrate. In the experiment, the researchers used many compounds, for example, (2S,4S)-Pentane-2,4-diylbis(diphenylphosphine) (cas: 77876-39-2Safety of (2S,4S)-Pentane-2,4-diylbis(diphenylphosphine)).

(2S,4S)-Pentane-2,4-diylbis(diphenylphosphine) (cas: 77876-39-2) belongs to chiral phosphine ligands. Although many reactions require more nucleophilic trialkylphosphines as catalysts, only a few chiral trialkylphosphines are available. Chiral ligands coordinate to metal centers to create an asymmetric environment around the reaction centers, which eventually affects enantioselectivity and reaction rate.Safety of (2S,4S)-Pentane-2,4-diylbis(diphenylphosphine)

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Palladium-catalyzed asymmetric carbamoyl-carbonylation of alkenes was written by Feng, Ziwen;Li, Qiuyu;Chen, Long;Yao, Hequan;Lin, Aijun. And the article was included in Science China: Chemistry in 2021.Name: (R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine) This article mentions the following:

An unprecedented palladium-catalyzed asym. carbamoyl-carbonylation of tethered alkenes with CO and alcs. was developed. This reaction provided an efficient route to access oxindoles I [R¹ = Me, Ph, 2-thienyl, etc.; R² = Me, i-Pr, Bn; R³ = Me, Et, CH₂CH₂TMS, etc.] and γ-lactams bearing β-carbonyl substituted quaternary carbons II [Ar = Ph, 3-MeC₆H₄, 4-MeOC₆H₄, 4-CF₃C₆H₄, 3-ClC₆H₄, 4-ClC₆H₄] in good yields with excellent chemo-, regio- and enantioselectivity. Gram-scale synthetic capability and facile transformations of the products to chiral spirooxindole and other functional mols. further illustrated the practicability of this reaction. In the experiment, the researchers used many compounds, for example, (R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine) (cas: 133545-16-1Name: (R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine)).

(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. Indeed, very little research on chiral tertiary phosphine-catalyzed asymmetric reactions occurred prior to the year 2000.Name: (R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine)

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis

Low-pressure Cobalt-Catalyzed Enantioselective Hydrovinylation of Vinylarenes was written by Movahhed, Sohajl;Westphal, Julia;Dindaroglu, Mehmet;Falk, Anna;Schmalz, Hans-Guenther. And the article was included in Chemistry – A European Journal in 2016.Formula: C24H20NO3P This article mentions the following:

An efficient and practical protocol for the enantioselective cobalt-catalyzed hydrovinylation of vinylarenes with ethylene at low (1.2 bar) pressure was developed. As precatalysts, stable [L₂CoCl₂] complexes were employed that were activated in situ with Et₂AlCl. A modular chiral TADDOL-derived phosphine-phosphite ligand was identified and that allowed the conversion of a broad spectrum of substrates including heterocyclic vinylarenes and vinylferrocene to smoothly afford the branched products with up to 99 % ee and virtually complete regioselectivity. Even polar functional groups such as OH, NH₂, CN, and CO₂R were tolerated. In the experiment, the researchers used many compounds, for example, (S)-4-(Dinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-yl)morpholine (cas: 185449-81-4Formula: C24H20NO3P).

(S)-4-(Dinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-yl)morpholine (cas: 185449-81-4) belongs to chiral phosphine ligands. At present, the synthesis of new chiral phosphines designed specifically for nucleophilic organocatalysis remains a significant challenge. Most of these phosphines are acyclic, usually possess low nucleophilic activity, and generally display poor enantioselectivities for phosphine organocatalysis. Formula: C24H20NO3P

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis