Palladium Phosphine Complexes Research Articles

Palladium catalyzed coupling reactions of β-perfluoroalkyl-substituted alkyl halides with organostannanes

β-Perfluoroalkyl-substituted alkyl halides reacted with organostamnanes such as allylphenylethynyl-, β-phenylethenyl-, and phenyl-tributyltin in the presence of palladium-phosphine complexes to give the corresponding cross-coupling products in good yields. When the reaction was carried out under CO pressure, carbonylative coupling of the halides took place affording the corresponding fluorine-contaming ketones in good yields.

Synthesis of new bis[p-(phenylethynyl)phenyl]hetarylenes and bis[p-(phenylglyoxalyl)phenyl]hetarylenes

A series of new bis[p-(phenylethynyi)phenyl]hetarylenes was obtained by cross-coupling between heteroaromatic dibromides and phenylacetylene catalyzed by phosphine complexes of palladium in the presence of Cul and an organic base. Bis[p-(phenylethynyl)phe-nyl]hetarylenes were oxidized to the corresponding bis[p-(phenylglyoxalyl)phenylihetarylenes using the I2-DMSO system.

First palladium-catalyzed Heck reactions with efficient colloidal catalyst systems

For the first time it has been shown that palladium colloids are effective and active catalysts for the olefination of aryl bromides (Heck reaction). Worthy of note are the high activities of the catalyst system for activated aryl bromides under optimized reaction conditions, which are better than or comparable with “classical” palladium phosphine complexes. Addition of phosphines strongly retards the reaction rate of the colloid catalyst. Nevertheless, this type of catalyst is not suitable for the activation of non-activated substrates, especially technically interesting aryl chlorides.

Palladium complex catalyzed SiSi bond metathesis dimerization of 3,4-benzo-1,2-dimethyl-1,2-diethyl-1,2-disilacyclobut-3-ene and isomerization of the resulting and relevant dimers

Palladium-phosphine complex catalyzed SiSi bond metathesis dimerization of 3,4-benzo-1,2-dimethyl-1,2-diethyl-1,2-disilacyclobut-3-ene ( 1b) took place at 80°C to give 3,4,7,8-dibenzo-1,2,5,6-tetramethyl-1,2,5,6-tetraethyl-1,2,5,6-tetrasilacycloocta-3,7-diene ( 2b) and its isomer 4,5,7,8-dibenzo-1,2,3,6-tetramethyl-1,2,3,6-tetraethyl-1,2,3,6-tetrasilacycloocta-4,7-diene ( 3b). Higher temperatures or longer reaction times enhanced the selectivity for 3b relative to 2b, indicative of concomitant isomerization of initially formed 2b to 3b. Isomerization of 3,4,7,8-dibenzo-1,1,2,2,5,5,6,6-octamethyl-1,2,5,6-tetrasilacycloocta-3,7-diene ( 2a), analogous to 2b, also proceeded at 80°C in the presence of Pd(PPh 3) 4. Besides 4,5,7,8-dibenzo-1,1,2,2,3,3,6,6-octamethyl-1,2,3,6-tetrasilacycloocta-4,7-diene ( 3a), 4,5-benzo-1,1,2,3,3-pentamethyl-2-( o-trimethylsilylphenyl)-1,2,3-trisilacyclopentene ( 4a), 3,4,6,7-dibenzo-1,1,2,2,5,5-hexamethyl-1,2,5-trisilacycloheptadiene ( 5a) and 4,5-benzo-1,1,2,2,3,3,-hexamethyl-1,2,3-trisilacyclopentene ( 6a) were also formed. Mechanisms of the dimerization of 1b and isomerization of 2a and 2b are discussed.

ChemInform Abstract: Two‐Phase Catalysis by Hydrophilic Phosphine Complexes of Palladium

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform Abstract: Water‐Soluble Palladium(II) Phosphine Complexes as Catalysts in the Hydrodehalogenation of Allyl and Benzyl Halogenides Under Biphasic and Phase‐Transfer Conditions.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Photoreactions of Palladium Phosphine Complex with Chloroalkane. Production of Ethylene with 1,2-Dichloroethane and Novel Photochromic Behavior

Abstract Photoirradiation on [Pd02(dppm)3] (dppm = bis(diphenylphosphino)methane) in 1,2-dichloroethane solution with visible light yields [PdI2Cl2(dppm)2] (2) and ethylene quantitatively. Irradiation of 2 in various solutions shows interesting photochromic behavior.

Catalytic carbonylation of ethylene in the presence of the Pd(acac)2-m-Ph2PC6H4SO3Na(H)-AcOH system

Catalytic systems based on phosphine complexes of palladium have been developed for synthesizing propionic acid (monocarbonylation) and alternating (1∶1) ethylene-carbon monoxide copolymers,i.e., polyketones (polycarbonylation).m-(Diphenylphosphino)benzenesulfonic acid or its sodium salt were used as ligands. Monocarbonylation proceeds at atmospheric pressure in dioxane or acetic acid solvents. Under high pressure, the reaction pathway can change from monocarbonylation, which occurs in the presense of the sodium salt of the ligand, to polycarbonylation when the sodium ion at the sulfo group is completely replaced by a proton. This change in reaction selectivity is observed when the process is performed in acetic acid. When the ligand is present both in the acid and the neutral form, products of di- and oligocarbonylation are formed along with propionic acid and the polyketone. These products were characterized by1H and13C NMR spectra as alternating keto acids C2H5(COCH2CH2) n COOH, wheren=1÷3. Kinetic equations were derived for the selective synthesis of propionic acid and polyketones.

Ethoxycarbonylation of 4,4'-Dihalobiphenyl Derivatives Catalyzed by Palladium-phosphine Complexes.

Effects of phosphines on palladium catalyzedethoxycarbonylation of 4, 4'-dihalobiphenyl derivatives under high pressure of carbon monoxide were studied in the presence of amine and ethanol. In ethoxycarbonylation of 4, 4'-dibromobiphenyl (Ia), the presence of excess triphenylphosphine (Ph3P) ligand over palladium promoted selective formation of diethyl biphenyl-4, 4'-dicarboxylate (IIa), however, palladium complex with low Ph3P/Pd ratios gave ethyl 4'-bromobiphenyl-4-carboxylate (IIIa) selectively. Chelate diphosphines, 1, 3-bis(diphenylphosphino)propane (dppp) and 1, 4-bis(diphenylphosphino)-butane (dppb) produced palladium complexes having much higher activities than Ph3P in ethoxycarbonylation of several 4, 4'-dibromobiphenyl derivatives. Ia, 2, 7-dibromo-9, 10-dihydrophenanthrene (Ib), 2, 7-dibromofluorene(Ic), and 2, 7-dibromofluorenone (Id) quantitatively yielded their corresponding diesters by using Pd-dppp catalysts. Mechanisms of the palladium catalyzed reactions are discussed.

A new facile synthesis of 2-substituted 1,3-butadiene derivatives via palladium-catalyzed cross-coupling reaction of 2,3-alkadienyl carbonates with organoboron compounds

A synthesis of 2-aryl-, 2-(1-alkenyl)-, and 2-alkyl-1,3-butadiene derivatives ( 2) by the palladium-catalyzed cross-coupling reaction of 2,3-butadienyl carbonates ( 1) with 9-alkyl-9-bicyclo[3.3.1]nonanes (9-alkyl-9-BBN), 1-alkenylboronic acids, or arylboronic acids is described. The reaction proceeded regioselectively with the palladium-phosphine complexes under neutral conditions.

パラジウム‐水溶性ホスフィン錯体による二相系触媒反応

Water-soluble complex catalysts are useful because of simple separation from the products, high activity, and selectivity. To conduct palladium-catalyzed reactions under liquid-liquid two-phase conditions, water-soluble polyether- or crown ether-substituted phosphines with phase transfer ability have been synthesized and characterized. The following reactions in aqueous media catalyzed by the water-soluble phosphine complexes of palladium are surveyed. (1) Hydrogenolysis of allylic halides with formate proceeds smoothly under liquid-liquid or liquid-solid two-phase conditions and 1-olefins are formed. In the two-phase catalysis the palladium complex itself plays a role of a phase transfer agent and a mechanism of inverse phase transfer process has been proposed. Benzylic halides are reduced similarly. (2) Allylic and benzylic halides are carbonylated under atmospheric pressure in aqueous NaOH/organic solvent system to afford β, γ-unsaturated acid and phenylacetic acid, respectively. (3) The reaction of bromoarenes possessing electron-withdrawing groups with ethylene (the Heck reaction) is also possible in an aqueous phase.

Preparation of Palladium(II) and Platinum(II) Phosphine Complexes Promoted by Phase‐Transfer Catalysts

AbstractThe synthesis of M(PR3)2Cl2 (M = Pd and Pt, R = alkyl or aryl) front K2MCl4 (in H2O) and PR3 (in CH2Cl2) was promoted by the addition of phase‐transfer catalysts (PTC). The greater the amount of PTC used, the more quickly the reaction completed. 31P NMR spectra of some M(PR3)2Cl2 in the presence of free PR3 were measured; these NMR resulls were used to explain problems encountered during the preparations.

Optical resolutions and chelating properties of (.+-.)-[2-(methylsulfinyl)ethyl]diphenylarsine and its phosphorus analog

An optical resolution of the asymmetric chelating agents (±)-(Ph 2 ECH 2 CH 2 S(O)Me] (E=As or P) has been achieved via fractional crystallization of a pair of diastereomeric palladium(II) complex cations containing the appropriatesulfinyl-substituted ligand and ortho-metalated (S)-(1-(dimethylamino)ethyl)naphthalene. The crystal and molecular structure of the perchlorate salt of the less soluble phosphine-palladium complex has been determined. Crystal data: monoclinic pale yellow prisms, P2 1 , a=10.147(2) A, b=10.955(2) A, c=26.888(5) A, β=97.76(2) o , Z=4, and R=0.0302

ChemInform Abstract: Hydrophosphination of Formaldehyde Catalyzed by Tris(hydroxymethyl) phosphine Complexes of Platinum, Palladium or Nickel.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Hydrophosphination of formaldehyde catalysed by tris-(hydroxymethyl)phosphine complexes of platinum, palladium or nickel

The addition of PH3 to formaldehyde to give P(CH2OH)3 is catalysed by a range of platinum-(IV), -(II) and -(0) compounds including Na2[PtCl6], K2[PtCl4], [PtCl2{P(CH2OH)3}2]2 and [Pt{P(CH2OH)3}4]·H2O 3. A large ratio of P(CH2OH)3 to Pt is present under the conditions in which the catalysis is operated and the hypothesis that a common platinum–P(CH2OH)3 complex is present under these conditions has been tested. It is shown that Na2[PtCl6] is reduced by 3 equivalents of P(CH2OH)3 to give [PtCl2{P(CH2OH)3}2]2, the same species that is formed upon addition of 2 equivalents of P(CH2OH)3 to K2[PtCl4]. Addition of 1 equivalent of P(CH2OH)3 to 2 gives [PtCl{P(CH2OH)3}]3Cl 4a while addition of 2 equivalents of P(CH2OH)3 to 2 gives an unstable species, tentatively assigned the five-co-ordinate structure [PtCl{P(CH2OH)3}4]Cl 5a. In the presence of further P(CH2OH)3, 5a decomposes smoothly to give a mixture of [PtH{P(CH2OH)3}4]Cl 3b, [P(CH2OH)4]Cl and the unusual bis(chelate) salts trans- and cis-[Pt{(HOCH2)2PCH2OP(CH2OH)2}2]Cl26a and 6b. A mechanism rationalising this reaction is presented. The pH of the reaction medium during the catalysis is ca. 9–10 and it is therefore concluded that [Pt{P(CH2OH)3}4]3a is the main platinum-containing species present during all the platinum catalysed reactions. It is shown that [Ni{P(CH2OH)3}4]18 and [Pd{P(CH2OH)3}4]19 are also catalysts for the hydrophosphination of formaldehyde and a general mechanism is suggested.

Water-soluble palladium(II)phosphine complexes as catalysts in the Hydrodehalogenation of Allyl and Benzyl Halogenides under biphasic and phase transfer conditions

Water soluble palladium(II) complexes of the type PdCl2(phosphine)2 with sulfonated phosphines as ligands catalyse the reductive dehalogenation of allyl or benzyl halogenides by means of formates in a biphasic water/heptane system. This reaction can be promoted by addition of polyethers of different types as phase transfer catalysts. Enhancement of reaction rate and control of selectivity are investigated in the reductive conversion of (E)-Ph-CH CHCH2Cl leading to (E)-Ph-CH CH-CH3 and Ph-CH2-CH CH2.

パラジウム触媒を用いる新しいタイプの重合反応

It has been well documented that palladium complexes catalyze versatile and useful reactions. Contemplation of these reactions from the standpoint of polymer synthesis has brought new polymerizations, which are reviewed in this article including topics of ring-opening polymerization, polycondensation, polyaddition, and addition polymerization. 1) A new type of ring-opening polymerization, whose key intermediates were π-allyl palladium complexes, was developed. Especially, for the polymerization of cyclic carbamates was designed and achieved an unusual mode that propagating ends multiply at every step of propagation. The produced polyamines had hyperbranched dendritic structures incorporating the initiator as the core. 2) Aromatic polymers such as poly (phenylene vinylene) s, polyphenylenes, and polyamides were prepared by the Heck reaction and Pd-catalyzed cross-coupling reactions. 3) Electrophilic palladium complexes initiated vinyl polymerizations of styrene, methyl propiolate, norbornene, etc. as well as alternating copolymerizations of some alkenes with carbon monoxide. Bromo (methyl) palladium-phosphine complexes initiated living aromatization polymerizations of 1, 2-diisocyanoarenes. 4) A cyclic compound having a Si-Si bond, 1, 2-disilacyclopentane, was polymerized with the aid of a Pd (0) complex.

Palladium-catalyzed aryloxycarbonylation of terminal alkynes

Carbonylation of terminal alkynes using palladium-phosphine complexes proceeds efficiently in the presence of 3- or 4-substituted phenols to give the corresponding 2-substituted 2-propenoic acid aryl esters in good selectivity and yield.

Fluoride-induced reduction of palladium(II) and platinum(II) phosphine complexes

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTFluoride-induced reduction of palladium(II) and platinum(II) phosphine complexesM. R. Mason and J. G. VerkadeCite this: Organometallics 1992, 11, 6, 2212–2220Publication Date (Print):June 1, 1992Publication History Published online1 May 2002Published inissue 1 June 1992https://doi.org/10.1021/om00042a040RIGHTS & PERMISSIONSArticle Views1529Altmetric-Citations75LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (1 MB) Get e-AlertsSupporting Info (1)»Supporting Information Supporting Information Get e-Alerts

Synthesis of ?,?-disubstituted aldehydes involving metallated 1-aza-1,3-butadienes in the presence of phosphine complexes of palladium

A novel catalytic method was developed for the synthesis ofα,β-disubstituted aldehydes by the reaction of N-, O-, and S−containing allyl electrophiles with magnesium azaenolates obtained by metallation ofα,β-unsaturated imines by Grignard reagents. The reaction is carried out with high regio- and stereoselectivity in the presence of phosphine complexes of palladium.