- Catalytic Cleavage of Unactivated C(aryl)-P Bonds by Chromium
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We describe here the coupling to transform aryl phosphine derivatives by the cleavage of unactivated C(aryl)-P bonds with chromium catalysis, allowing us to achieve the reaction with alkyl bromides and arylmagnesium reagents under mild conditions. Mechani
- Ling, Liang,Luo, Meiming,Tang, Jinghua,Yuan, Shuqing,Zeng, Xiaoming
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p. 1581 - 1586
(2022/03/14)
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- Decarboxylative Phosphine Synthesis: Insights into the Catalytic, Autocatalytic, and Inhibitory Roles of Additives and Intermediates
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Phosphines are among the most widely used ligands, catalysts, and reagents. Current synthetic approaches to phosphines are dominated by nucleophilic displacement reactions with organometallic reagents. Here, we report a radical-based approach to phosphines that proceeds by a cross-electrophile coupling of chlorophosphines and redox-active esters. The reaction allows for the synthesis of a broad range of substituted phosphines that were not readily attainable with the present methods. Our experimental and DFT computational studies also clarified the catalytic, autocatalytic, and inhibitory roles of additives and intermediates, as well as the mechanistic details of the photocatalytic and zinc-mediated redox modes that can have implications for the mechanistic interpretation of other cross-electrophile coupling reactions.
- Jin, Shengfei,Haug, Graham C.,Nguyen, Vu T.,Flores-Hansen, Carsten,Arman, Hadi D.,Larionov, Oleg V.
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p. 9764 - 9774
(2019/10/14)
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- SPIROCYCLIC COMPOUNDS AS FARNESOID X RECEPTOR MODULATORS
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The present invention provides compounds of Formula (I): or stereoisomers, tautomers, or pharmaceutically acceptable salts or solvates thereof, wherein all the variables are as defined herein. These compounds modulate the activity of famesoid X receptor (FXR), for example, as agonists. This invention also relates to pharmaceutical compositions comprising these compounds and methods of treating a disease, disorder, or condition associated with FXR dysregulation, such as pathological fibrosis, transplant rejection, cancer, osteoporosis, and inflammatory disorders, by using the compounds and pharmaceutical compositions.
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Paragraph 0667
(2019/05/15)
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- Highly Efficient and Robust Photocatalytic Systems for CO2 Reduction Consisting of a Cu(I) Photosensitizer and Mn(I) Catalysts
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The development of highly efficient, selective, and durable photocatalytic CO2 reduction systems that only use earth-abundant elements is key for both solving global warming and tackling the shortage of energy and carbon resources. Here, we successfully developed CO2 reduction photocatalysts using [Cu2(P2bph)2]2+ (CuPS) (P2bph = 4,7-diphenyl-2,9-di(diphenylphosphinotetramethylene)-1,10-phenanthroline) as a redox photosensitizer and fac-Mn(X2bpy)(CO)3Br (Mn(4X)) (X2bpy = 4,4′-X2-2,2′-bipyridine (X = -H and -OMe) or Mn(6mes) (6mes = 6,6′-(mesityl)2-2,2′-bipyridne)) as the catalyst. The most efficient photocatalysis was achieved by Mn(4OMe): The total quantum yield of CO2 reduction products was 57%, the turnover number based on the Mn catalyst was over 1300, and the selectivity of CO2 reduction was 95%. Electronic and steric effects of the substituents (X) in the Mn complexes largely affected both the photocatalytic efficiency and the product selectivity. For example, the highest selectivity of CO formation was achieved by using Mn(6mes) (selectivity SCO = 96.6%), whereas the photocatalytic system using Mn(4H) yielded HCOOH as the main product (SHCOOH = 74.6%) with CO and H2 as minor products (SCO = 23.7%, SH2 = 1.7%). In these photocatalytic reactions, CuPS played its role as an efficient and very durable redox photosensitizer, while remaining stable in the reaction solution even after a turnover number of 200 had been reached (the catalyst used had a turnover number of over 1000).
- Takeda, Hiroyuki,Kamiyama, Hiroko,Okamoto, Kouhei,Irimajiri, Mina,Mizutani, Toshihide,Koike, Kazuhide,Sekine, Akiko,Ishitani, Osamu
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p. 17241 - 17254
(2019/01/04)
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- Organocatalyzed Reduction of Tertiary Phosphine Oxides
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A novel selective catalytic reduction method of tertiary phosphine oxides to the corresponding phosphines has been developed. Notably, the reaction proceeds smoothly with low catalyst loadings of 1-5 mol% even at low temperature (70 C). Under the optimized conditions various phosphine oxides could be selectively reduced and the desired phosphines were usually obtained in excellent yields above 90%. Furthermore, we have developed a one-pot reaction sequence for the preparation of valuable phosphinborane adducts. Simple addition of BH3THF subsequent to the reduction step gave the desired adducts in yields up to 99%.
- Schirmer, Marie-Luis,Jopp, Stefan,Holz, Jens,Spannenberg, Anke,Werner, Thomas
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supporting information
p. 26 - 29
(2016/01/25)
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- Direct conversion of phosphonates to phosphine oxides: An improved synthetic route to phosphines including the first synthesis of methyl JohnPhos
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The synthesis of tertiary phosphine oxides from phosphonates was achieved reliably and in good to excellent yields using stoichiometric amounts of alkyl or aryl Grignard reagents and sodium trifluoromethanesulfonate (NaOTf). In the absence of the NaOTf additive, covalent coordination oligomers of magnesium and phosphorus species dominate the reaction, producing very low yields of phosphine oxide, but high conversions of the phosphonate starting material. Mechanistic studies revealed that a five-coordinate phosphorus species - not a phosphinate - is the reaction intermediate. A diverse array of phosphonates was converted to phosphine oxides using a variety of Grignard reagents for direct carbon-phosphorus functionalization. This new methodology especially simplifies the synthesis of dimethylphosphino (RPMe2)-type phosphines by using air-, water-, and silica-stable intermediates. To highlight this reaction, a new Buchwald-type ligand ([1,1′-biphenyl]-2-yldimethylphosphine, or methyl JohnPhos) and a classic bidentate phosphine, bis(diphenylphosphino)propane (dppp), were synthesized in excellent yields.
- Kendall, Alexander J.,Salazar, Chase A.,Martino, Patrick F.,Tyler, David R.
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p. 6171 - 6178
(2015/02/19)
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- General and selective copper-catalyzed reduction of tertiary and secondary phosphine oxides: Convenient synthesis of phosphines
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Novel catalytic reductions of tertiary and secondary phosphine oxides to phosphines have been developed. Using tetramethyldisiloxane (TMDS) as a mild reducing agent in the presence of copper complexes, PO bonds are selectively reduced in the presence of other reducible functional groups (FGs) such as ketones, esters, and olefins. Based on this transformation, an efficient one pot reduction/phosphination domino sequence allows for the synthesis of a variety of functionalized aromatic and aliphatic phosphines in good yields.
- Li, Yuehui,Das, Shoubhik,Zhou, Shaolin,Junge, Kathrin,Beller, Matthias
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supporting information; experimental part
p. 9727 - 9732
(2012/07/14)
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- Highly chemoselective metal-free reduction of phosphine oxides to phosphines
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Unprecedented chemoselective reductions of phosphine oxides to phosphines proceed smoothly in the presence of catalytic amounts of specific Br?nsted acids. By utilizing inexpensive silanes, e.g., PMHS or (EtO)2MeSiH, other reducible functional groups such as ketones, aldehydes, olefins, nitriles, and esters are well-tolerated under optimized conditions.
- Li, Yuehui,Lu, Liang-Qiu,Das, Shoubhik,Pisiewicz, Sabine,Junge, Kathrin,Beller, Matthias
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p. 18325 - 18329
(2013/01/15)
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- Reduction of phosphine oxides to phosphines with the InBr3/TMDS system
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An efficient method for the reduction of phosphine oxide derivatives into their corresponding phosphines is described. The system InBr3/TMDS allows the reduction of different secondary and tertiary phosphine oxides as well as aliphatic and aromatic phosphine oxides.
- Pehlivan, Leyla,Métay, Estelle,Delbrayelle, Dominique,Mignani, Gérard,Lemaire, Marc
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supporting information; experimental part
p. 3151 - 3155
(2012/05/31)
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- The synthesis and deep purification of GaEt3. Reversible complexation of adducts MAlk3 (M = Al, Ga, In; Alk = Me, Et) with phenylphosphines
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Optimal parameters of organomagnesium technique of synthesis of triethylgallium have been defined. Various techniques of deep purification of triethylgallium to the extent required in metalorganic vapor-phase epitaxy MOVPE have been studied: by way of residue ether displacement through high-performance rectification and interaction with high pure aluminum and gallium trichloride, and by way of reversible complexation with triphenylphosphine, 1,3-bis(diphenylphosphine)propane and 1,5- bis(diphenylphosphine)pentane. Advantages and disadvantages of each technique have been identified. We have shown high performance of adduct purification technique covering trimethyl and triethyl derivatives of aluminum, gallium and indium. The structure of donor-acceptor complexes between metal alkyls and the above-mentioned phosphines have been verified using H and 31P NMR spectroscopy and X-ray studies, as well as quantum chemical calculations. Thermal stability of triethylgallium and oxidation of its adducts with phosphines have been studied.
- Shatunov,Korlyukov,Lebedev,Sheludyakov,Kozyrkin,Orlov, V.Yu.
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experimental part
p. 2238 - 2251
(2011/06/22)
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- Catalyst-free alcoholysis of phosphane-boranes: a smooth, cheap, and efficient deprotection procedure
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Catalyst-free alcoholytic deprotection of borane-protected phosphorus compounds offers a smooth, efficient, and clean alternative to existing deprotection methods. In this paper we report our results on the general applicability of deprotecting phosphane-
- Van Overschelde, Michel,Vervecken, Elias,Modha, Sachin G.,Cogen, Simon,Van der Eycken, Erik,Van der Eycken, Johan
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experimental part
p. 6410 - 6415
(2009/12/09)
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- A catalytic method for the reduction of secondary and tertiary phosphine oxides
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TMDS has been found to be an efficient hydride source for the reduction of tertiary and secondary phosphine oxides using a catalytic amount of Ti(Oi-Pr)4. All classes of tertiary phosphine oxides, such as triaryl, trialkyl, and diphosphine, were effectively reduced. Georg Thieme Verlag Stuttgart.
- Berthod, Mika?l,Favre-Réguillon, Alain,Mohamad, Jahjah,Mignani, Gérard,Docherty, Gordon,Lemaire, Marc
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p. 1545 - 1548
(2008/02/05)
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- METHOD FOR PRODUCING TERTIARY PHOSPHINES
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The invention relates to a method for producing tertiary phosphines by reacting a compound of general formula (I) with (a) an alkali metal in an organic aprotic solvent and (b) a compound of general formula (II). In formula (I), A represents R1 or L2, B represents R2 or L3, where the groups R1 and R2 independently of one another stand for an organic group with respectively between 1 and 30 carbon atoms and said groups R1 and R2 can also be bonded together. The leaving groups L1 to L3 independently of one another represent halogen, alkyloxy with between 1 and 10 carbon atoms or aryloxy with between 6 and 10 carbon atoms. In formula (II), the group R3 represents an organic group with respectively between 1 and 30 carbon atoms and the leaving group L4 represents halogen, alkyloxy with between 1 and 10 carbon atoms or aryloxy with between 6 and 10 carbon atoms. The reaction mixture that is obtained is hydrolysed using an aqueous base with a pH value of > 10 and the organic phase is then separated from the aqueous phase.
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Page/Page column 19-20
(2008/06/13)
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- A mild and efficient CsOH-promoted synthesis of ditertiary phosphines
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A mild and efficient method for the synthesis of ditertiary phosphines has been developed. In the presence of cesium hydroxide, molecular sieves, and DMF, various dihalides were coupled with diphenylphosphine at room temperature, and the results have demonstrated that this methodology offers a general synthetic procedure producing a variety of ditertiary phosphines in high yields.
- Honaker, Matthew T.,Salvatore, Ralph Nicholas
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p. 277 - 283
(2007/10/03)
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- CsOH-promoted P-alkylation: A convenient and highly efficient synthesis of tertiary phosphines
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A mild and efficient method for the synthesis of tertiary phosphines and ditertiary phosphines has been developed. In the presence of cesium hydroxide, molecular sieves and DMF at room temperature, various secondary phosphines and alkyl bromides were examined, and the results have demonstrated that this methodology offers a general synthetic procedure to produce tertiary phosphines in moderate to high yields. Optically active tertiary phosphine synthesis is also described.
- Honaker, Matthew T.,Sandefur, Benjamin J.,Hargett, James L.,McDaniel, Alicia L.,Salvatore, Ralph Nicholas
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p. 8373 - 7377
(2007/10/03)
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- Preparation of organohalosilanes
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When oganohalosilanes are prepared by charging a reactor with a contact mass containing a metallic silicon powder and a copper catalyst, and introducing an organohalide-containing gas into the reactor to effect the direct reaction, a poly(organo)phosphino compound is added to the contact mass. The invention is successful in producing organohalosilanes at a significantly improved production rate without reducing the selectivity of useful silane.
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- Method for producing benzoic acid derivatives
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The invention relates to a method for producing a benzoic acid derivative represented by the general formula (1). The method includes the step of reacting an aromatic compound represented by the general formula (2), with carbon monoxide and a hydroxy compound (i.e., water or an alcohol), in the presence of (a) a metal compound containing a metal of 8, 9 and 10 groups of periodic table, (b) a first phosphine derivative represented by the general formula (R1)2P—Q—P(R1)2, and (c) a base, It is possible to easily and efficiently produce the benzoic acid derivative by the method.
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- Process for the preparation of substituted phenols
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A process for the preparation of substituted phenols, in particular, the condensation of phenols having one or more alkyl substituents with a butadiene derivative comprising at least six carbon atoms, in particular myrcene and/or β-springene is disclosed. The cyclization, in the form of chromans, of the products obtained during this condensation and their hydrogenation in order to prepare vitamin E is also disclosed.
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- Method for manufacturing acryloxypropysilane
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A method to manufacture acryloxypropylsilane to a high degree of purity is achieved by hydrosilation of (A) allyl acrylate or allyl methacrylate by (B) a hydrosilane compound, using (C) a platinum-containing compound as the catalyst and (D) an organic phosphorus compound as the promoter. The acryloxypropylsilane product is expressed by General Formula I where R1 represents a hydrogen or methyl group, R2 represents a hydrolyzable group, R3 represents an aryl, alkenyl or aryl group of carbon number 1-12, and n is 0, 1, 2, or 3.
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- Structure of diiodine adducts of some di- and tri-tertiaryphosphines in the solid state and in solution
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A series of ditertiaryphosphine-tetraiodine adducts R2P(I2)(CH2)nP(I2)R 2 (R = Ph, n = 1-4; R = PhCH2 or o-CH3C6H4, n = 2) and two tritertiaryphosphine-hexaiodine adducts, PhP(CH2CH2PPh2)2I6 and CH3C(CH2-PPh2)3I6 have been prepared and characterised by 31P-{H} solution NMR and Raman spectroscopy. In the case of Ph2P(I2)(CH2)nP(I 2)Ph2 (n = 2 or 4), 31P-{H} NMR magic angle spinning NMR spectroscopy has been used to investigate the nature of the compounds in the solid state. In agreement with our previous extensive studies on the monophosphine derivatives, R3PI2, the tetraiododiphosphine compounds Ph2P(I2)(CH2)nP(I 2)Ph2 (n = 2 or 4) isolated from diethyl ether contain molecular four-co-ordinate phosphorus centres onto which the diiodine is bound as a linear spoke, as indicated by their 3IP-{H} NMR shifts obtained in CDCl3 solution. Again, in agreement with our previous solution studies of the monophosphine derivatives R3PI2, the diphosphine-tetraiodine adducts completely ionise in CDCl3 solution to produce the ionic compounds [R2P(I)(CH2)nP(I)R2]2I; the solution 31P-{H} NMR shifts are very similar to analogous solution shifts previously assigned to [R3PI]I. The Raman band assignable to v(P-I) has been identified for the compounds and a further band at lower frequency has been observed and assigned to v(I-I). Although the solid-state NMR spectra of the triphosphine-hexaiodine adducts were not recorded, a band assignable, to v(I-I) was observed in the Raman spectrum, suggesting the molecular four-co-ordinate spoke structure also prevails for these hexaiodotritertiaryphosphine compounds in the solid state. From solution 31P-{H} NMR shifts these adducts also appear to ionise in CDCl3 solution.
- Bricklebank, Neil,Godfrey, Stephen M.,McAuliffe, Charles A.,Deplano, Paula,Mercuri, Marie L.,Sheffield, Joanne M.
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p. 2379 - 2382
(2007/10/03)
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- ZUR REAKTION VON PHOSPHORVERBINDUNGEN MIT SCHWESINGER BASEN-I P-C-BINDUNGKNUEPFUNG AN P-H-FUNKTIONELLEN PHOSPHORVERBINDUNGEN
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Secondary and tertiary phosphines (RR'PH; R2R'P) may be synthesized by alkylation of primary or secondary phosphines with organo halides (R' = Et, n-C7H15, Bz, Me3Si; X = Cl, Br) in the presence of Schwesinger bases as auxillary bases in high yields.Alkylation of diphenylphosphine with alkylene dihalides and Schwesinger bases affords alkylendiphosphines. Key words: Alkylation; secondary and tertiary phosphines; Schwesinger bases.
- Uhlig, Frank,Puschner, Beatrix,Herrmann, Eckhard,Zobel, Bernhard,Bernhardt, Henry,Uhlig, Wolfram
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p. 155 - 164
(2007/10/02)
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- Process for the preparation of ketones
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A process for the preparation of ketones which comprises reacting a conjugated diolefin and water in the liquid phase in the presence of a catalyst system comprising: a) a group VIII metal compound, and b) a source of protons.
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- Radical Cations of Bis(diphenylphosphino) Derivatives (Ph2P-R-PPh2): The Formation of Localized, Cyclic, and Dimeric Configurations. An ESR and Quantum Chemical Study
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A matrix ESR study on radiogenic radical cations of Ph2P-R-PPh2 derivatives with various linkers (R) is presented.The experiments show that in a frozen dichloromethane solution the radical cations can adopt localized (Ph2PR*+), cyclic , and dimeric (Ph2RP*-PRPh2+) configurations, depending on the nature of the linker.The cyclic and dimeric products are formed in the reaction of a localized cation with a second free-electron pair, resulting in an intra- or intermolecular three-electron P-P ?* bond, respectively.The formation of the cyclic structure, with a strongly bent P-P ?* bond, requires a specific proximate position of the two phosphine moieties in the precursor molecule.The mutual orientation of the two free-electron pairs of the precursors is assessed by NMR via the nJPP spin-spin coupling constant.Ab initio UHF quantum chemical calculations at the 3-21G*/SCF level support the assignments.
- Janssen, Rene A. J.,Aagaard, Olav M.,Cabbolet, Marcoen J. T. F.,Waal, Bas F. M. de
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p. 9256 - 9263
(2007/10/02)
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- Preparation of vinylphosphines by means of free radical addition of diphenylphosphine to alkynes and allenes
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Diphenylphosphine adds readily to alkynes and allenes under free radical conditions.Alkynes normally give E-vinylphosphines as the primary (kinetic) product, but Z-vinylphosphines are the main products isolated.Allenes generally give complex product mixtures in which the predominant components are vinyl phosphines formed via addition of the Ph2P. radical to the central carbon atom of the allene fragment.
- Mitchell, Terence N.,Heesche, Kerstin
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p. 163 - 170
(2007/10/02)
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- Process for the preparation of lactones from higher alkenols
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Process for the preparation of lactones, having 4 or 5 carbon atoms in the ring by reacting a higher alkenol with a carbon monoxide containing gas in the presence of a catalytic system comprising (a) a palladium compound, (b) a bidentate phosphine, arsine and/or stibine, and (c) a protonic acid having a pKa 2.
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- Efficient 1,4-Asymetric Induction Utilizing Electrostatic Interaction between Ligand and Substrate in the Asymmetric Hydrogenation of Didehydrodipeptides
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Electrostatic interaction between the amino group of the achiral 3-dimethylaminopropylidenebismethylenebis(diphenylphosphine) (1) and the carboxy group of the substrate enable an effective 1,4-asymmetric induction in the RhI-catalysed hydrogenation of didehydrodipeptides, to give (S,S)-or (R,R)-products selectively.The selectivity reached up to 94percent diastereoisomeric excess with acetyl didehydrodipeptides and 92percent with benzyloxycarbonyl substrates.
- Yamagishi, Takamichi,Ikeda, Satoru,Yatagai, Masanobu,Yamaguchi, Motowo,Hida, Mitsuhiko
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p. 1787 - 1790
(2007/10/02)
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- Process for the preparation of aldehydes
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Process for the preparation of aldehydes by hydroformylation of an alkenically unsaturated compound in the presence of (a) Pd, a Pd compound, Pt and/or a Pt compound, (b) an anion of a carboxylic acid with a pKa 1 R2 -M-R-M-R3 R4, wherein M is P, As or Sb, R is a divalent organic bridging group having at least 3 carbon atoms in the bridge, and R1, R2, R3 and R4 are hydrocarbon groups.
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- Process for the coproduction of anilines and oxamides
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A process for the coproduction of anilines of the formula wherein X is a halogen atom, an alkyl-, alkoxy-, aryloxy-, cyano-, ester- or trifluoromethyl group and n is an integer from 0 to 5, and oxamides of the formula wherein each R independently is an alkyl group which comprises reacting an aromatic nitro compound of the general formula wherein X and n are as defined above with carbon monoxide and a molar excess in relation to the nitro compound of an amine HNR2 wherein R is an alkyl group, in the presence of a catalyst system comprising (a) palladium metal or a compound thereof, (b) a bidentate ligand of the formula, R1R2--M--A--M--R3R4, in which M is P, As or Sb, A is a divalent organic bridging group having at least 2 carbon atoms in the bridge, none of these carbon atoms carrying substituents that may cause steric hindrance, and R1,R2,R3 and R4 represent similar or dissimilar optionally substituted hydrocarbon groups, and (c) an acid or a transition metal salt of said acid.
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- Process for the carbonylation of ethylenically unsaturated compounds
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Process for the preparation of a carboxylic ester or acid by reacting an ethylenically unsaturated compound in which each of the carbon atoms of the carbon-carbon double bond is secondary or tertiary, with CO in the presence of an alkanol or water, respectively, and of a catalytic system prepared by combining:-, a) Pd and/or a Pd compound, b) a strong acid, except hydrohalogenic and carboxylic acids, and c) a bidentate ligand, using a molar ratio of acid to ligand of greater than 0.5.
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- Process for the preparation of urea derivatives and catalyst system
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The invention relates to a process for the preparation of urea derivatives of the general formula wherein R is an alkyl group and X is a halogen atom, an alkyl-, alkoxy-, aryloxy-, cyano-, ester- or trifluoromethyl group and n is from 0 to 5,which comprises reacting an aromatic nitro compound of the general formula wherein X and n are as defined above with carbon monoxide and an amine HNR2 wherein R is an alkyl group,in the presence of a catalyst system comprising (a) a group VIII noble metal or a compound thereof, (b) a bidentate ligand and (c) an acid having a pKa of more than 2 or a transition metal salt of said acid.
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- Production of primary and secondary amines by reaction of ammonia with conjugated diene in the presence of Pd/phosphine catalyst and primary or secondary aliphatic alcohol solvent medium
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Short chain, unsaturated primary and secondary amines are prepared by reaction of ammonia and conjugated dienes in a primary or secondary aliphatic alcohol solvent medium and in the presence of a catalyst system comprising a palladium compound co-catalyzed with a phosphine ligand containing 2 to 4 phosphorus atoms.
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