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Palladium complexes carbonylation

In hydrocarboxylation, the Reppe reaction, the catalyst can be nickel or cobalt carbonyl or a palladium complex where R = H or alkyl. [Pg.63]

Allylation of perfluoroalkyl halides with allylsilanes is catalyzed by iron or ruthenium carbonyl complexes [77S] (equation 119) Alkenyl-, allyl-, and alkynyl-stannanes react with perfluoroalkyl iodides 111 the presence ot a palladium complex to give alkenes and alkynes bearing perfluoroalkyl groups [139] (equation 120)... [Pg.478]

Styrene, a-ethyl-asymmetric hydroformylation catalysts, platinum complexes, 6, 266 asymmetric hydrogenation catalysts, rhodium complexes, 6, 250 Styrene, a-methyl-asymmetric carbonylation catalysis by palladium complexes, 6, 293 carbonylation... [Pg.226]

Palladium complexes also catalyze the carbonylation of halides. Aryl (see 13-13), vinylic, benzylic, and allylic halides (especially iodides) can be converted to carboxylic esters with CO, an alcohol or alkoxide, and a palladium complex. Similar reactivity was reported with vinyl triflates. Use of an amine instead of the alcohol or alkoxide leads to an amide. Reaction with an amine, AJBN, CO, and a tetraalkyltin catalyst also leads to an amide. Similar reaction with an alcohol, under Xe irradiation, leads to the ester. Benzylic and allylic halides were converted to carboxylic acids electrocatalytically, with CO and a cobalt imine complex. Vinylic halides were similarly converted with CO and nickel cyanide, under phase-transfer conditions. ... [Pg.565]

Sparteine 1 was also used in a palladium complex-catalyzed enantios-elective benzoylation of alcohols using monoxide and the organobismuth(V) compound (Scheme 37). The carbonylative acylation of alcohols using carbon monoxide (CO) is known to be an alternative tool for the prepar-... [Pg.83]

Following this pnblication, the anthors tested a series of Pd-NHC complexes (33-36) for the oxidative carbonylation of amino compounds (Scheme 9.8) [44,45]. These complexes catalysed the oxidative carbonylation of amino compounds selectively to the nreas with good conversion and very high TOFs. Unlike the Cu-NHC catalyst 38-X, the palladium complexes catalysed the oxidative carbonylation of a variety of aromatic amines. For example, 35 converted d-Me-C H -NH, d-Cl-C H -NH, 2,4-Me3-C H3-NH3, 2,6-Me3-C H3-NH3, and 4-Ac-C H3-NH3 to the corresponding nreas with very high TOFs (>6000) in 1 h at 150°C, in 99%, 87%, 85%, 72%, and 60% isolated yields, respectively (Pco,o2 = 3.2/0.8 MPa). [Pg.228]

Cavell KJ, McGuinness DS (2007) Palladium complexes with carbonyl, isocyanide and carbene ligands. In Crabtree RH, Mingos DMP, Canty AJ (eds) Comprehensive organometallic chemistry 111. Elsevier, Amsterdam... [Pg.313]

The allylation of aldehydes can be carried out using stannous chloride and catalytic cupric chloride or copper in aqueous media." In-situ probing provides indirect (NMR, CV) and direct (MS) evidence for the copper(I)-catalyzed formation of an allyltrihalostannane intermediate in very high concentration in water (Scheme 8.6). Hydrophilic palladium complex also efficiently catalyzes the allylation of carbonyl compounds with allyl chlorides or allyl alcohols with SnCl2 under aqueous-organic... [Pg.233]

Dixon, K. R. Dixon, A. C. Palladium Complexes with Carbonyl, Isocyanide and Carbene Ligands, In Comprehensive Organometallic Chemistry II A review of the literature 1982-1994 Puddephatt, R. J. Ed., Elsevier, 1995, Vol. 9, p 193. [Pg.663]

Me3SiPdSnBu3 is formed primarily from 6/1-237, which then adds to the allene moiety in 6/1-236 to give a a- or Jt-allyl palladium complex. This undergoes an intramolecular carbonyl allyl addition to afford the cis-cycloalkariols 6/1-238 (Scheme 6/1.61). [Pg.398]

In reactions closely related to the carbonylation processes described above, the dimeric azoarene palladium complexes (78) can be transformed efficiently in two steps into 3-imino-2-phenylindazolines (Scheme 95).162... [Pg.361]

The mercuration of phosphonium derivatives has also been observed. The methylene group of the dimeric palladium complex 63 substituted by a carbonyl and a phosphonium functionality is readily mercurated upon reaction with Hg(OAc)2 to afford complex 64 (Equation (22)).7 Further studies demonstrated that the presence of a triphenylphosphonium group alone is sufficient to promote proton-mercury exchange. For example, the reaction of... [Pg.428]

The carbonylation was explained by the following mechanism. Formation of dimeric 7r-allylic complex 20 from two moles of butadiene and the halide-free palladium species is followed by carbon monoxide insertion at the allylic position to give an acyl palladium complex which then collapses to give 3,8-nonadienoate by the attack of alcohol with regeneration of the zero-valent palladium phosphine complex. When halide ion is coordinated to palladium, the formation of the above dimeric 7r-allylic complex 20 is not possible, and only monomeric 7r-allylic complex 74 is formed. Carbon monoxide insertion then gives 3-pentenoate (72). [Pg.166]

Not only do palladium complexes catalyze reactions of Eq. (58), but nickel complexes were also effective (51) and formed the same products. Complexes such as Fe(CO)5 and Fe2(CO)8 were ineffective. Cobalt carbonyl, and tris-triphenylphosphinerhodium chloride were effective even at room temperature, but no 2 1 adducts were made. With both palladium and nickel, the activity of the catalyst and the distribution of products between 1 1 and 2 1 adducts is greatly dependent on the nature of the donor ligands on the metal. [Pg.442]

The a-arylation of carbonyl compounds (sometimes in enantioselective version) such as ketones,107-115 amides,114 115 lactones,116 azlactones,117 malonates,118 piperidinones,119,120 cyanoesters,121,122 nitriles,125,124 sul-fones, trimethylsilyl enolates, nitroalkanes, esters, amino acids, or acids has been reported using palladium catalysis. The asymmetric vinylation of ketone enolates has been developed with palladium complexes bearing electron-rich chiral monodentate ligands.155... [Pg.314]

Besides rhodium catalysts, palladium complex also can catalyze the addition of aryltrialkoxysilanes to a,(3-unsaturated carbonyl compounds (ketones, aldehydes) and nitroalkenes (Scheme 60).146 The addition of equimolar amounts of SbCl3 and tetrabutylammonium fluoride (TBAF) was necessary for this reaction to proceed smoothly. The arylpalladium complex, generated by the transmetallation from a putative hypercoordinate silicon compound, was considered to be the catalytically active species. [Pg.395]

Y. Kayaki, Y. Noguchi, S. Iwasa, T. Ikariya, R. Noyori, An Effitient Carbonylation of Aryl Halides Catalysed by Palladium Complexes with Phosphite Ligands in Supercritical Carbon Dioxide , Chem Commun. 1999, 1235-1236. [Pg.25]

Under appropriate conditions, alcohols and amines can undergo an oxidative double carbonylation process, with formation of oxalate esters (Eq. 34), oxamate esters (Eq. 35) or oxamides (Eq. 36). These reactions are usually catalyzed by Pd(II) species and take place trough the intermediate formation of bis(alkoxycarbonyl)palladium, (alkoxycarbonyl)(carbamoyl)palladium or bis(carbamoyl)palladium complexes, as shown in Scheme 29 (NuH, Nu H = alcohol or amine) [227,231,267,293-300]. [Pg.260]

In a slightly less convenient procedure, but one which has general versatility, carbonylation of aryl (or vinyl) palladium compounds produces aryl, heteroaryl, and vinyl carboxylic acids. As with the other procedures, immediate upon its formation, the carboxylate anion migrates to the aqueous phase. Consequently, haloaromatic acids can be obtained from dihaloarenes, without further reaction of the second halogen atom, e.g. 1,4-dibromobenzene has been carbonylated (90% conversion) to yield 4-bromobenzoic acid with a selectivity for the monocarbonylation product of 95%. Additionally, the process is economically attractive, as the organic phase containing the catalyst can be cycled with virtually no loss of activity and ca. 4000 moles of acid can be produced for each mole of the palladium complex used [4],... [Pg.383]


See other pages where Palladium complexes carbonylation is mentioned: [Pg.156]    [Pg.75]    [Pg.81]    [Pg.87]    [Pg.88]    [Pg.95]    [Pg.121]    [Pg.127]    [Pg.127]    [Pg.203]    [Pg.204]    [Pg.226]    [Pg.563]    [Pg.1035]    [Pg.228]    [Pg.259]    [Pg.589]    [Pg.78]    [Pg.154]    [Pg.182]    [Pg.190]    [Pg.194]    [Pg.232]    [Pg.318]    [Pg.709]    [Pg.1344]    [Pg.212]    [Pg.158]    [Pg.186]   
See also in sourсe #XX -- [ Pg.280 ]

See also in sourсe #XX -- [ Pg.92 , Pg.228 , Pg.233 ]

See also in sourсe #XX -- [ Pg.429 ]

See also in sourсe #XX -- [ Pg.280 ]

See also in sourсe #XX -- [ Pg.6 , Pg.280 ]




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Carbonyl complexes of palladium

Cationic palladium complexes alkyne carbonylation

Palladium carbonyl complexes

Palladium carbonyl complexes

Palladium carbonylation

Palladium carbonylations

Palladium carbonyls

Palladium complexes carbonylation reactions

Palladium complexes oxidative carbonylation

Palladium®) complexes carbonylation, natural products synthesis

Styrene, a-methylasymmetric carbonylation catalysis by palladium complexes

Styrene, a-methylasymmetric carbonylation catalysts, palladium complexes

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