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Palladium , catalysis

Commonly, the first step in palladium-catalyzed cross-coupling reactions is the oxidative addition of an organohalide or triflate to a Pd species. While numerous catalytic systems exist for the activation of C(sp )-I and C(sp )-Br bonds, due to their increased stability, activation of C(sp )-Cl bonds is a considerably greater challenge. The use of NHCs as ancillary ligands in these types of reactions has allowed the use of aryl chlorides as coupling partners under relatively mild conditions. From these substrates, experimental and [Pg.105]

Consistent with the high catalytic activity of PdL type systems, a multitude of in situ generated catalytic systems have shown repeatedly that the optimal Pd/NHC ratio is However, there are scattered reports in which the [Pg.106]

Though methods exist for the synthesis of [(NHQPd ] complexes, pal-ladium(0) species are rarely employed as pre-catalysts due to the requirement for rigorously anaerobic and anhydrous conditions. Amongst the few examples of air-stable [(NHC)Pd ] catalysts are those reported by Seller and co-workers featuring diene ° or quinone auxiliary ligands. Pd° precursors, on the other hand, are often far more robust and can be handled with greater ease, but then of course must be activated in situ to produce the catalytically active [(NHQPd ] species. [Pg.107]


Transition-Metal Catalyzed Cyclizations. o-Halogenated anilines and anilides can serve as indole precursors in a group of reactions which are typically cataly2ed by transition metals. Several catalysts have been developed which convert o-haloanilines or anilides to indoles by reaction with acetylenes. An early procedure involved coupling to a copper acetyUde with o-iodoaniline. A more versatile procedure involves palladium catalysis of the reaction of an o-bromo- or o-trifluoromethylsulfonyloxyanihde with a triaLkylstaimylalkyne. The reaction is conducted in two stages, first with a Pd(0) and then a Pd(II) catalyst (29). [Pg.87]

Reduction of Acid Chlorides to Aldehydes. Palladium catalysis of acid chlorides to produce aldehydes is known as the Rosenmund reduction and is an indirect method used in the synthesis of aldehydes from organic acids. [Pg.200]

Four-membered heterocycles can be formed by the addition of isocyanides to 1,3-dipoles (80AG(E)45) and by the reaction of carbon monoxide with -haloamines, with the aid of palladium catalysis (Scheme 10) (79CC699). [Pg.36]

CH2=C(OBn)CH2F, PdCl2(COD), CH3CN, it, 24 h, 89-100% yield. Protic acids can also be used to introduce this group, but the yields are sometimes lower. A primary alcohol can be protected in the presence of a secondary alcohol. This reagent also does not give cyclic acetals of 1,3-diols with palladium catalysis. [Pg.40]

In the first chapter, N. M. Ahmad and J. J. Li (Pfizer, Ann Arbor, USA) discuss the use of palladium in quinoline synthesis, thus filling an important gap in a recent monograph on the uses of palladium catalysis in heterocyclic synthesis authored by the same group. This is followed by an account of pyrimidine-pyridine interconversions by H. C. van der Plas (Wageningen University, The Netherlands) the immense variety of heterocyclic chemistry is illustrated by the large number of diverse strategies for such transformations. [Pg.357]

The synthesis of thiepins 14 was unsuccessful in the case of R1 = i-Pr,79 but if the substituents in the ortho positions to sulfur arc /erf-butyl, then thiepin 14 (R1 = t-Bu R2 = Me) can be isolated in 99% yield.80 Rearrangement of diazo compound 13 (R1 = t-Bu R2 = H), which does not contain the methyl group in position 4, catalyzed by dimeric ( y3-allyl)chloropalladium gives, however, the corresponding e.w-methylene compound. The thiepin 14 (R1 = t-Bu, R2 = H) can be obtained in low yield (13 %) by treatment of the diazo compound with anhydrous hydrogen chloride in diethyl ether at — 20 C.13 In contrast, the ethyl thiepin-3,5-or -4,5-dicarboxylates can be prepared by the palladium catalysis method in satisfying yields.81... [Pg.85]

Synthesis of isomeric chiral protected (63 )-6-amino-hexahydro-2,7-dioxopyrazolo[l,2- ]pyrazole-l-carboxylic acid 280 is shown in Scheme 36. Crude vinyl phosphonate 275, obtained by treatment of diethyl allyloxycarbonylmethyl-phosphonate with acetic anhydride and tetramethyl diaminomethane as a formaldehyde equivalent, was used in the Michael addition to chiral 4-(f-butoxycarbonylamino)pyrazolidin-3-one 272. The Michael addition is run in dichloro-methane followed by addition of f-butyl oxalyl chloride and 2 equiv of Huning s base in the same pot to provide 276 in 58% yield. The allyl ester is deprotected using palladium catalysis to give the corresponding acid 277, which is... [Pg.407]

The molybdenum-catalyzed asymmetric reaction differs from the palladium-catalyzed reaction in several ways, the most important of which is the different regios-electivity achieved. Molybdenum-catalyzed reactions favor the most sterically hindered position (Eq. 11.39), in contrast with palladium catalysis. The molybdenum-catalyzed allylations also suffer from significantly lower reactivity. [Pg.398]

Allyl sulphones can be converted to dienes by alkylation and elimination of sulphinic acid under basic conditions (equation 64)105. Several vitamin A related polyenes have been synthesized following this two-step protocol (Table 10)106. The poor leaving-group ability of the arylsulphonyl group requires treatment with strong base for elimination. However, elimination of the allylsulphonyl group takes place readily under palladium catalysis (equation 65)107. Vinyl sulphones can be converted to dienes via Michael addition, alkylation with allyl halides and elimination of sulphinic acid sequence (equation 66)108. [Pg.394]

Bromoalkynes also couple with vinylstannanes readily to result in enynes. Synthesis of protected enynals via cross-coupling of vinylstannanes with 1-bromoalkynes in the presence of a catalytic amount of Pd(II) has been reported (equation 143)252. Hiyama and coworkers extended the Stille methodology for sequential three-component coupling of trimethylstannyl(trimethylsilyl)acetylene with a vinyl iodide in the first step and cross-coupling of the intermediate trimethylsilylethyne with another alkenyl iodide in the presence of tris(diethylamino)sulphonium trimethyldifluorosilicate in the second step to generate a dienyne (equation 144)253. Both steps occur under palladium catalysis, in one-pot, to result in stereodefined l,5-dien-3-ynes. [Pg.446]

Stewart and Whiting have reported a useful application of sequential Heck and Suzuki coupling reactions of a vinylborane pinacol ester with palladium catalysis to generate a tetraene (equation 147)260. [Pg.447]

AryT3,4-fused furans 63 are synthesized in moderate to good yields from propargyl nucleophiles and a-sulfonyl a,p-unsaturated ketones under palladium catalysis conditions... [Pg.142]

Similar results for the replacement of halogen on an olefinic linkage by phosphorus have been accomplished using dialkyl phosphites with palladium(O) catalysts.4179 Another reaction involving replacement of a vinylic halide by phosphorus utilizes palladium catalysis with a trimethylsilyl-substituted phosphine (Figure 6.19).80... [Pg.175]

Beletskaya IP, Cheprakov AV (2000) The Heck reaction as a sharpening stone of palladium catalysis. Chem Rev 100 3009-3066... [Pg.95]

A cascade reaction involving multiple C-H functionalizations has been employed for the formation of bicyclic heterocycles with palladium catalysis (Equation (160)).134... [Pg.150]

The palladium-catalyzed arylation of 2-phenylphenols and naphthols shows an interesting feature of arylation of C-H bonds, leading to the formation of an (aryl)(aryloxy)palladium(n) intermediate.65,65a,65b The phenolates are suitable as precoordinating groups. The reaction of 2-hydroxybiphenyl with an excess of iodobenzene occurs regioselectively at the two ortho-positions of phenyl group under palladium catalysis (Equation (57)). In the case of 1-naphthol, the peri-position is phenylated (Equation (58)). [Pg.227]

The arylation of heteroaromatic compounds is also achieved by aryl-aryl coupling reaction. The arylation of A-methylimidazole with bromobenzene occurs under palladium catalysis (Equation (62)).72 The arylation of thiazole with aryl iodide occurs at the 2-position under PdCl2(PPh3)2/CuI catalysis.73 In this case, tetrabutylammonium fluoride improves the activity of the catalyst. Alternatively, thiazoles and benzothiazole are efficiently arylated... [Pg.227]

The intramolecular arylation of sp3 C-H bonds is observed in the reaction of l-/ r/-butyl-2-iodobenzene under palladium catalysis (Equation (71)) 94 94a 94b The oxidative addition of Arl to Pd(0) gives an ArPdl species, which undergoes the electrophilic substitution at the tert-butyl group to afford the palladacycle. To this palladacycle, another molecule of Arl oxidatively adds, giving the Pd(iv) complex. [Pg.231]

Trost reported the synthesis of 1,4-dienes with ruthenium catalysis through regioselective carbometallation of alkynes with alkenes.51 Di- and trisubstituted olefins can also be obtained with arylboronic acids through an intermolecular process under rhodium,30 52 55 nickel,56 and palladium catalysis.57 Recently, Larock has reported an efficient palladium-catalyzed route for the preparation of tetrasubstituted olefins.58,59... [Pg.304]

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]

Platinum-catalyzed allylation of aldehydes with allyltin reagents was first reported in 1995.4S7 457b,483 483a Ar0matiC) aliphatic, a,/3-unsaturated aldehydes and even cyclohexanone undergo allylation with allyltributyltins in the presence of PtClgtPP 113)2 >n THF at room temperature or higher temperature (Equations (123) and (124)). Allylplatinum species are considered to be the active intermediates on the basis of related mechanistic studies on palladium catalysis. [Pg.470]

Butylallene, which fails to react with (PhSe)2 under palladium catalysis, undergoes the diselenide addition upon photo-irradiation (Equation (80)).215 Using the (PhS)2/(PhSe)2 binary system, introduction of two different chalcogen elements into allenic C=C bond is also viable (Equation (81)). [Pg.758]

For a review of the use of palladium catalysis in heterocycle synthesis, with a good summary of the authors work, see Sakamoto, T. Kondo, Y. Yamanaka, H. Heterocycles 1988,27,2225-49. [Pg.171]

Lin and Yamamoto described a Pd-catalyzed carbonylation of benzyl alcohols [131]. Thus, under the agency of palladium catalysis and promotion by HI, 3-thiophenemethanol was carbonylated to give 3-thiopheneacetic acid as a major product along with methylthiophene as a minor one. [Pg.258]

The formation of an s/Z-hybridized C—P bond is readily achievable using the Michaelis-Arbuzov reaction. Such an approach is not applicable to form heteroaryl C—P bonds in which the carbon atoms are sp2 hybridized, whereas palladium catalysis does provide a useful method for Csp2—P bond formation. The first report on Pd-catalyzed C—P bond formation was revealed by Hirao et al. [134-136]. Xu s group further expanded the scope of these reactions [137, 138], They coupled 2-bromothiophene with n-butyl benzenephosphite to form n-butyl arylphosphinate 161 [137]. In addition, the coupling of 2-bromothiophene and an alkylarylphosphinate was also successful [138], For the mechanism, see page 19-21. [Pg.259]

With palladium catalysis, both 2,6-dichloropyrazine 3 and chloropyrazine N-oxide 5 were methylated using trimethylaluminum to give adducts 4 and 6, respectively [7,8]. [Pg.356]

T.A. Chen and R.D. Rieke, The first regioregular head-to-tail poly(3-hexylthiophene-2,5-diyl) and a regiorandom isopolymer nickel versus palladium catalysis of 2(5)-bromo-5(2)- (bromozincio)-3-hexylthiophene polymerization, J. Am. Chem. Soc., 114 10087-10088, 1992. [Pg.282]


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1,3-Pentadiene, 5-aminosynthesis via palladium catalysis

1.3- Cyclooctadiene palladium catalysis

1.6- Enynes palladium catalysis

Acetaldehyde palladium catalysis

Acetals palladium catalysis

Acetophenone, methoxytin chloride complexes palladium complex catalysis

Acetophenones palladium catalysis

Acid chlorides palladium complex catalysis

Acylation palladium catalysis

Alcohols palladium catalysis

Alkenes palladium catalysis

Alkylation palladium catalysis

Alkylations palladium catalysis

Allenes palladium catalysis

Allyl acetates palladium catalysis

Allyl carbamates palladium catalysis

Allyl carbonates, 2- cycloaddition palladium catalysis

Allyl carbonates, methylcycloaddition palladium catalysis

Allyl chloride palladium catalysis

Allyl esters palladium catalysis

Allyl palladium catalysis

Allylamines palladium catalysis

Allylic alkylation palladium catalysis

Allylic substitutions palladium catalysis

Amino sugars via palladium catalysis

Aminocarbonylation palladium catalysis

Aqueous conditions palladium catalysis

Arylation palladium catalysis

Azaspirocycles via palladium catalysis

Benzaldehyde, 4-acetylacylation palladium complex catalysis

Bridged carbocyclic systems via palladium catalysis

Bromination palladium catalysis

Butene catalysis by palladium complexes

Carbocyclization palladium catalysis

Carbonyl compounds oxidation, palladium catalysis

Carbonyl compounds synthesis, palladium catalysis

Carboxylic acids palladium catalysis

Catalysis Induced by Platinum and Palladium Nanoparticles

Catalysis Mostly Palladium

Catalysis palladium-catalyzed alkynylation

Catalysis with molybdenum-palladium

Chlorination palladium catalysis

Cope rearrangements palladium catalysis

Cumulative Subject palladium catalysis

Cyanohydrin anions alkenes, palladium catalysis

Cyclization arylative, palladium catalysis

Cyclization-carbonylation palladium catalysis

Cyclohex-2-ene, trans-1 -acetoxy-4-trifluoroacetoxysynthesis via palladium catalysis

Cyclooctadienes palladium catalysis

Diamination palladium catalysis

Dienes palladium catalysis

Direct catalysis palladium catalysts

Electrochemical oxidation palladium catalysis

Electron-deficient palladium catalysis

Enamines palladium catalysis

Ene diones via palladium catalysis

Ethers palladium catalysis

Ethers, allyl palladium catalysis

Furans via alkynes, palladium catalysis

Grignard reagents halides, palladium catalysis

Heck reaction aqueous palladium catalysis

Heteroatomic coupling palladium catalysis

Heteroatomic nucleophiles palladium catalysis

Hydrosilylation palladium catalysis

Ibogamine via palladium catalysis

Indoles via alkynes, palladium catalysis

Iodination palladium catalysis

Ketenes palladium catalysis

Ketones, methyl via palladium catalysis

Lithium, phenyladdition reactions alkenes, palladium catalysis

Malonate, 5-methyl -decenylcyclization palladium catalysis

NHC-palladium complexes in catalysis

Nucleophilic aromatic palladium catalysis

Nucleophilic substitution palladium®) catalysis

Organocopper reagents palladium catalysis

Organomercury reagents palladium catalysis

Organometallic compounds palladium catalysis

Organostannanes palladium complex catalysis

Organozinc reagents palladium catalysis

Other Palladium Catalysis in Ionic Liquids

Oxidative addition palladium catalysis

Oxy-Cope reactions palladium catalysis

Palladium Catalysis for Oxidative 1,2-Difunctionalization of Alkenes

Palladium Catalysis in Ionic Liquids

Palladium Catalysis in the Synthesis of Benzo-Fused Heterocycles

Palladium Vinylidenes in Catalysis

Palladium acetate, catalysis

Palladium catalysis Alkene alkylation

Palladium catalysis Alkene amination

Palladium catalysis Alkene carbonylation

Palladium catalysis Claisen rearrangement

Palladium catalysis Heck reaction

Palladium catalysis Heck, aryl iodides

Palladium catalysis Negishi reaction

Palladium catalysis Pauson-Khand reactions

Palladium catalysis Pd

Palladium catalysis Sonogashira

Palladium catalysis Sonogashira reaction

Palladium catalysis Subject

Palladium catalysis Suzuki-Miyaura

Palladium catalysis Suzuki-Miyaura reaction

Palladium catalysis Suzuki/Heck reactions

Palladium catalysis addition

Palladium catalysis addition-elimination reactions

Palladium catalysis aerobic oxidation

Palladium catalysis alkene acetalization

Palladium catalysis alkenylation

Palladium catalysis alkynylation

Palladium catalysis allylation

Palladium catalysis allylation, alkynes

Palladium catalysis allylic

Palladium catalysis allylic alkylations

Palladium catalysis amination

Palladium catalysis aromatic

Palladium catalysis aromatic substitution

Palladium catalysis aryl bromides

Palladium catalysis aryl halide reactions

Palladium catalysis arylation/oxidation

Palladium catalysis arylboronic acid

Palladium catalysis aryne reactions

Palladium catalysis asymmetric hydrogenation

Palladium catalysis biaryl formation

Palladium catalysis biaryl products

Palladium catalysis carbamate reactions

Palladium catalysis carbocyclizations

Palladium catalysis carbonylation

Palladium catalysis coupling

Palladium catalysis cross-coupling

Palladium catalysis cross-coupling reactions

Palladium catalysis cyanation

Palladium catalysis cyclisation reactions

Palladium catalysis cyclization

Palladium catalysis cycloaddition

Palladium catalysis cycloisomerization

Palladium catalysis cyclopropane ring

Palladium catalysis decarboxylative allylation

Palladium catalysis dehydrogenative coupling

Palladium catalysis electrophilic

Palladium catalysis electrophilic addition

Palladium catalysis enantioselective allylic alkylation

Palladium catalysis group

Palladium catalysis halogenation

Palladium catalysis heterocyclization, reviews

Palladium catalysis homocoupling

Palladium catalysis hydroamination

Palladium catalysis hydrodechlorination

Palladium catalysis hydrogenation

Palladium catalysis in the total synthesis of a natural alkaloid

Palladium catalysis intramolecular

Palladium catalysis isomerization

Palladium catalysis ligand-free

Palladium catalysis nucleophilic

Palladium catalysis of arenes

Palladium catalysis of indoles

Palladium catalysis of pyridines

Palladium catalysis olefination, oxygen oxidant

Palladium catalysis olefinations

Palladium catalysis oxidation

Palladium catalysis oxidation with

Palladium catalysis oxygenation

Palladium catalysis palladacycles

Palladium catalysis phosphonation

Palladium catalysis reaction

Palladium catalysis rearrangements

Palladium catalysis reduction

Palladium catalysis review

Palladium catalysis silane reactions

Palladium catalysis silane synthesis

Palladium catalysis solvent effects

Palladium catalysis substitution

Palladium catalysis sulfone synthesis

Palladium catalysis sulfuration

Palladium catalysis trifluoromethylation

Palladium catalysis vinyl substitution

Palladium catalysis vinylation

Palladium catalysis, dehydrogenation

Palladium catalysis, general discussion

Palladium complex catalysis

Palladium complex catalysis asymmetric

Palladium complex catalysis hydrogenation

Palladium complex catalysis reductive

Palladium complex catalysis telomerization

Palladium complex catalysis with methanol

Palladium complexes dinuclear. catalysis

Palladium mediated catalysis

Palladium, dichlorobis catalysis

Palladium, dichlorobis catalysis halide carbonylation

Palladium, phenylbis catalysis arylmagnesium halide reaction with alkyl halides

Palladium-catalysis reaction types

Palladium®) complexes aqueous catalysis

Phenylation palladium catalysis

Phosphonium ylides, allylic tributylsynthesis via palladium catalysis

Pyran via palladium catalysis

Pyrroles via alkynes, palladium catalysis

Pyrroles via palladium catalysis

Quadrone via palladium catalysis

Reagents aqueous palladium catalysis

Solvents aqueous palladium catalysis

Styrene catalysis by palladium complexes

Styrene, a-methylasymmetric carbonylation catalysis by palladium complexes

Sulfides, homoallylic palladium catalysis

Suzuki coupling, palladium catalysis

Suzuki, Takamitsu Hosoya, and Ryoji Noyori TECHNOLOGICAL DEVELOPMENTS IN ORGANOPALLADIUM HEMISTRY l Aqueous Palladium Catalysis

Synthesis of Naproxen by Palladium Catalysis

Synthesis oxidation, palladium catalysis

Thioimidates, S-allylClaisen-type rearrangement palladium catalysis

Transition metal catalysis palladium chemistry

Transition metal catalysis, gold palladium

Unsupported palladium, catalysis

Vinyl acetate via palladium catalysis

Vinyl ethers via palladium catalysis

Wacker process palladium catalysis

Water-based reactions palladium catalysis

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