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Phosphine, ligands

Attention should be paid to the fact that the ratio of Pd and phosphine ligand in active catalysts is crucial for determining the reaction paths. It is believed that dba is displaced completely with phosphines when Pd2(dba)3 is mixed with phosphines in solution. However the displacement is not eom-plcte[16]. Also, it should be considered that dba itself is a monodentate alkene ligand, and it may inhibit the coordination of a sterically hindered olefinic bond in substrates. In such a case, no reaction takes place, and it is recommended to prepare Pd(0) catalysts by the reaction of Pd(OAc)2 with a definite amount of phosphinesflO]. In this way a coordinatively unsaturated Pd(0) catalyst can be generated. Preparation of Pd3(tbaa)3 tbaa == tribenzylidene-acetylacetone) was reported[17], but the complex actually obtained was Pd(dba)2[l8],... [Pg.3]

Fundamental reactions of Pd are briefly explained in order to understand how reactions either promoted or catalyzed by Pd proceed. In schemes written for the explanation, phosphine ligands are omitted for. simplicity. First, a brief explanation of chemical terms specific to organopalladium chemistry is given. [Pg.5]

Facile oxidative addition is possible with iodides and bromides. The reactions of iodides can be carried out even in the absence of a phosphine ligand,... [Pg.125]

The diazonium salts 145 are another source of arylpalladium com-plexes[114]. They are the most reactive source of arylpalladium species and the reaction can be carried out at room temperature. In addition, they can be used for alkene insertion in the absence of a phosphine ligand using Pd2(dba)3 as a catalyst. This reaction consists of the indirect substitution reaction of an aromatic nitro group with an alkene. The use of diazonium salts is more convenient and synthetically useful than the use of aryl halides, because many aryl halides are prepared from diazonium salts. Diazotization of the aniline derivative 146 in aqueous solution and subsequent insertion of acrylate catalyzed by Pd(OAc)2 by the addition of MeOH are carried out as a one-pot reaction, affording the cinnamate 147 in good yield[115]. The A-nitroso-jV-arylacetamide 148 is prepared from acetanilides and used as another precursor of arylpalladium intermediate. It is more reactive than aryl iodides and bromides and reacts with alkenes at 40 °C without addition of a phosphine ligandfl 16]. [Pg.148]

The benzoic acid derivative 457 is formed by the carbonylation of iodoben-zene in aqueous DMF (1 1) without using a phosphine ligand at room temperature and 1 atm[311]. As optimum conditions for the technical synthesis of the anthranilic acid derivative 458, it has been found that A-acetyl protection, which has a chelating effect, is important[312]. Phase-transfer catalysis is combined with the Pd-catalyzed carbonylation of halides[3l3]. Carbonylation of 1,1-dibromoalkenes in the presence of a phase-transfer catalyst gives the gem-inal dicarboxylic acid 459. Use of a polar solvent is important[314]. Interestingly, addition of trimethylsilyl chloride (2 equiv.) increased yield of the lactone 460 remarkabiy[3l5]. Formate esters as a CO source and NaOR are used for the carbonylation of aryl iodides under a nitrogen atmosphere without using CO[316]. Chlorobenzene coordinated by Cr(CO)j is carbonylated with ethyl formate[3l7]. [Pg.190]

Polyphenylene polymers can be prepared by this coupling. For example, the preparation of poly(/i-quaterphenylene-2,2 -dicarboxylic acid) (643) was carried out using aqueous NaHCO and a water-soluble phosphine ligand (DPMSPP)[5I I]. Branched polyphenylene was also prepared[5l2). [Pg.219]

The coupling of the enol triflate 703 with the vinylstannane 704[397] has been applied to the synthesis of glycinoeclepin[576]. The introduction of a (Z)-propenyl group in the / -lactam derivative 705 proceeds by use of tri-2-furylphosphine[577]. However, later a smooth reaction to give the propenyl-iactam in 82% yield was achieved simply by treating with Pd(OAc)2 in NMP or CH2CI2 for 3-5 min without addition of LiCI and the phosphine ligand[578]. [Pg.232]

Asymmetric allylation of carbon nucleophiles has been carried out extensively using Pd catalysts coordinated by various chiral phosphine ligands and even with nitrogen ligands, and ee > 90% has been achieved in several cases. However, in most cases, a high ee has been achieved only with the l,3-diaryl-substitiitcd allylic compounds 217, and the synthetic usefulness of the reaction is limited. Therefore, only references are cited[24,133]. [Pg.319]

Dimerization is the main path. However, trimerization to form 1.3,6,10-dodecatetraene (15) takes place with certain Pd complexes in the absence of a phosphine ligand. The reaction in benzene at 50 C using 7r-allylpalladium acetate as a catalyst yielded 1,3,6,10-dodecatetraene (15) with a selectivity of 79% at a conversion of 30% based on butadiene in 22 h[ 19,20]. 1,3,7-Octatriene (7) is dimerized to 1,5,7,10.15-hexadecapentaene (16) with 70% selectivity by using bis-rr-allylpalladium. On the other hand. 9-allyl-l,4,6.12-tridecatetraene (17) is formed as the main product when PI13P is added in a 1 1. ratio[21]. [Pg.425]

The reaction of methyl propionate and formaldehyde in the gas phase proceeds with reasonable selectivity to MMA and MAA (ca 90%), but with conversions of only 30%. A variety of catalysts such as V—Sb on siUca-alumina (109), P—Zr, Al, boron oxide (110), and supported Fe—P (111) have been used. Methjial (dimethoxymethane) or methanol itself may be used in place of formaldehyde and often result in improved yields. Methyl propionate may be prepared in excellent yield by the reaction of ethylene and carbon monoxide in methanol over a mthenium acetylacetonate catalyst or by utilizing a palladium—phosphine ligand catalyst (112,113). [Pg.253]

Molybdenum(0) also forms a variety of dinitrogen complexes (41), especially when there are phosphine ligands in the molybdenum coordination sphere (see Fig. 7c). This type of complex has been extensively studied because the coordinated dinitrogen is reduced to ammonia upon acidification. [Pg.474]

A further improvement in platinum catalysis is claimed from use of tin(Il) haUde and phosphine ligands which are rigid bidentates, eg, l,2-bis(diphenylphosphinomethyl)cyclobutane (27). High rates for a product containing 99% linear aldehyde have been obtained. However, a pressure of 10 MPa (1450 psi) H2 CO is requited. [Pg.470]

Heteroleptic complexes of uranium can be stabilized by the presence of the ancillary ligands however, the chemistry is dominated by methyl and benzyl ligands. Examples of these materials include UR4(dmpe) (R = alkyl, benzyl) and U(benzyl)4MgCl2. The former compounds coordinate "soft" chelating phosphine ligands, a rarity for the hard U(IV) atom. [Pg.335]

Figure 26.5 The laialyiic tyilc for ilic hydnifniinylaiion of an alkenc caralyicd hy TiJH-[RhHlCOjlPPh)j J The ici ciary phosphine ligand has been lepfcsemcd as P ihmughoui... Figure 26.5 The laialyiic tyilc for ilic hydnifniinylaiion of an alkenc caralyicd hy TiJH-[RhHlCOjlPPh)j J The ici ciary phosphine ligand has been lepfcsemcd as P ihmughoui...

See other pages where Phosphine, ligands is mentioned: [Pg.317]    [Pg.345]    [Pg.2701]    [Pg.2703]    [Pg.2]    [Pg.3]    [Pg.44]    [Pg.126]    [Pg.128]    [Pg.130]    [Pg.138]    [Pg.147]    [Pg.153]    [Pg.363]    [Pg.435]    [Pg.511]    [Pg.100]    [Pg.252]    [Pg.469]    [Pg.469]    [Pg.182]    [Pg.55]    [Pg.43]    [Pg.167]    [Pg.110]    [Pg.261]    [Pg.79]    [Pg.158]    [Pg.494]    [Pg.542]    [Pg.587]    [Pg.1134]    [Pg.1135]    [Pg.157]   
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Amido phosphine ligands

Amino-phosphine ligands, catalyst

Asymmetric hydrogenation phosphine phosphoramidite ligands

Biaryl phosphine ligands

Bidentate phosphine ligand

Brief Historical Overview of P-Chirogenic Phosphine Ligands

CARBONYLS, PHOSPHINE COMPLEXES, AND LIGAND SUBSTITUTION REACTIONS

Catalysts containing phosphine ligands

Chiral ferrocene based phosphine phosphoramidite ligands

Chiral ligands bidentate phosphine

Chiral phosphine ligand

Chiral phosphine-phosphite ligands containing a stereocenter in the backbone

Cobalt phosphine ligands

Complexes containing phosphine ligands

Containing Orthometalated Phosphine Ligands

Copper complexes phosphine ligands

Coupling, organometallic phosphine ligands

Electron-rich, Sterically Hindered Phosphine Ligands

Electronic parameter phosphine ligand

Ferrocene phosphine ligands

Ferrocenyl phosphine ligands

First-Generation Ruthenium Indenylidene Catalysts Bearing Two Phosphine Ligands

Fluorinated phosphine ligand

Fluorous phosphine ligand

Gold phosphine ligands, homoleptic

Halogeno and isothiocyanato complexes with phosphine, phosphonite or arsine ligands

Heteroatom-substituted secondary phosphine oxide ligands

Hydridocobalt Complexes with Phosphine Ligands

Hydroformylation phosphine ligands

Hydrogenation of olefins with miscellaneous water-soluble catalysts without phosphine ligands

Hydrophilic phosphine ligands

Hydrosilylation phosphine ligands

Imidazole phosphine ligands

Indole-phosphine ligands

Initial Results with Phosphine Ligands

Ionic phosphine ligands

Iridium phosphine ligands

Iron compounds with phosphine ligands

Ligand chiral tertiary phosphine

Ligand complexes with phosphine

Ligand containing chiral phosphine

Ligand phosphine-rhodium complex

Ligand tertiary alkyl phosphines

Ligands aryl-phosphine

Ligands chiral phosphines, influence

Ligands furyl phosphines

Ligands monodentate phosphine

Ligands optically active phosphine

Ligands perfluoroalkylated phosphine

Ligands phosphine oxazoline

Ligands sulfonated phosphines

Ligands synthesis phosphine-acetals

Ligands synthesis phosphine-thioethers

Ligands trivalent phosphine

Mixed phosphine-arsine ligands

Molybdenum complexes phosphine ligands

Natural phosphine ligands

Negishi cross-coupling reactions phosphine ligands

Nitrogen-containing phosphine ligands

Olefin-phosphine hybrid ligands

Orthometalated phosphine ligand complexes

P-Chirogenic Phosphine Ligands

Palladium asymmetric allylic substitutions, phosphine ligands

Peptide-based phosphine ligand

Phosphinates as ligands

Phosphine Chalcogenides as Ligands

Phosphine aminophosphine ligands

Phosphine bridging ligands

Phosphine bridging ligands binuclear complexes with

Phosphine donor ligands, immobilized

Phosphine ligand-free direct

Phosphine ligand-free direct arylation

Phosphine ligands (PPh

Phosphine ligands 1758 INDEX

Phosphine ligands Bonding

Phosphine ligands Cone angle

Phosphine ligands Electron-donating properties

Phosphine ligands Electronic effects

Phosphine ligands Heck coupling reactions

Phosphine ligands Involvement

Phosphine ligands Pd

Phosphine ligands Suzuki-Miyaura reaction

Phosphine ligands acetate

Phosphine ligands acetylation

Phosphine ligands alkyl halide carbonylation

Phosphine ligands allylic compounds

Phosphine ligands allylic-phosphorus reactions

Phosphine ligands allylsilane

Phosphine ligands amination reactions

Phosphine ligands amino phosphines

Phosphine ligands aqueous catalysis

Phosphine ligands aryl halide formation

Phosphine ligands aryl halides

Phosphine ligands asymmetric

Phosphine ligands asymmetric hydroformylation

Phosphine ligands carbonylation

Phosphine ligands catalyst immobilization, polymer supports

Phosphine ligands cychzation

Phosphine ligands displacement

Phosphine ligands early studies

Phosphine ligands electron count

Phosphine ligands formation

Phosphine ligands hydrogenation

Phosphine ligands hydrometallation

Phosphine ligands iron complexes with

Phosphine ligands nucleophilic substitution

Phosphine ligands organic synthesis

Phosphine ligands palladium complexes

Phosphine ligands phosphorus coupling products

Phosphine ligands phosphorus-palladium complexes

Phosphine ligands preparation

Phosphine ligands reactions

Phosphine ligands steric parameters

Phosphine ligands sterically demanding

Phosphine ligands structural parameters

Phosphine ligands synthetic properties

Phosphine ligands transmetallation

Phosphine ligands zinc reagents

Phosphine ligands, commercially available

Phosphine ligands, ethylene

Phosphine ligands, ethylene insertion with

Phosphine ligands, exchange

Phosphine ligands, promotion

Phosphine ligands, technetium complexes

Phosphine ligands, tertiary

Phosphine ligands, water-soluble

Phosphine phosphinite ligands

Phosphine phosphoramidite ligands

Phosphine type ligands

Phosphine-Based Ligands

Phosphine-amine ligands

Phosphine-based copper ligands

Phosphine-metal complexes ligands

Phosphine-phosphite ligands

Phosphine-phosphoroamidite ligands

Phosphine-sulfoxide ligands

Phosphine/phosphite ligands, transition metal

Phosphine/polyphosphine ligands

Phosphines and Related Ligands

Phosphines as ligands

Phosphines bulky ligand condition

Phosphines carbon donor ligands

Phosphines difluorohalo, as ligand

Phosphines high-activity ligands

Phosphines ligand synthesis

Phosphines multidentate ligands

Phosphines nitrogen donor ligands

Phosphines oxygen donor ligands

Phosphines phosphine/phosphite-ligands

Phosphines phosphorus-nitrogen ligands

Phosphines phosphorus-sulfur ligands

Phosphines sulfur donor ligands

Phosphines, alkylation ligands

Phosphorus ligands tertiary phosphines

Poly(phosphine) Multidentate Ligands

Polydentate ligands phosphines

Primary phosphine ligands

Promotion by Phosphine Ligands and Derivatives

Reaction mechanism monodentate phosphine ligands

Rhodium catalysts phosphine-phosphite ligands

Rhodium complexes with phosphine ligands

Rhodium phosphine ligand anchored

Rhodium phosphine ligands

Rhodium sulfonated phosphine ligand

Rhodium-catalyzed hydrogenation phosphine ligands

Ruthenium metathesis catalysts phosphine ligand

Ruthenium phosphine ligands

Secondary phosphine ligands

Silicon ligands tertiary phosphines

Some New Insights into the Steric Effects of Tertiary Phosphine Ligands via Data Mining

Steric hindrance phosphine ligands

Subject phosphine ligands

Sulfonated phosphine and other ligands

Sulfonated phosphine ligands hydroformylation

Sulfonic acid phosphine ligands

Suzuki bulky phosphine ligands

Suzuki phosphine ligands

Suzuki water-soluble phosphine ligands

Synthesis and Complexation of Ethene Bridged Bis(phosphine) Ligands

TADDOL-derived phosphine/phosphite ligands

Technetium phosphine and arsine ligands

Tertiary Phosphines and Related Ligands

Tertiary phosphine ligands with nitrogen-containing substituents

Tertiary phosphine ligands with sulfonate or alkylene sulfate substituents

Tertiary phosphine-functionalized ligands

Tertiary phosphines, ancillary ligand

Tetradentate phosphine ligand

Tetrapodal phosphine ligand

Thiol ligand reaction with gold phosphines

Transition Metal Catalysts with Phosphine Ligands

Transition Metal Complexes Containing Bidentate Phosphine Ligands

Triphosphorus bidentate phosphine phosphoramidite ligands

Tris-phosphine ligands

Trisulfonated phosphine ligands

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