Phosphinates palladium

In related work, 3-chloromethylcephems were coupled with tributyl(tnfluoro-vinyl)stannane catalyzed by tri(2-furyl)phosphine palladium(O) [7S, 19] (equation 13). 

The palladium-catalyzed reaction of o-iodoanilides with terminal acetylenic carbinols provides a facile route to the synthesis of quinolines using readily available starting materials (93TL1625). When o-iodoanilide 126 was stirred with acetylenic carbinol 127 in the presence of bis-triphenyl phosphine palladium(ll) chloride in triethylamine at room temperature for 24 h, the substituted alkynol 128 was obtained in 65% yield. On cyclization of 128 with sodium ethoxide in ethanol, 2-substituted quinoline 129 was obtained in excellent yield. 

A solution of 1.5 mol equiv of butyllithium in hexane is added to 1.5 mol equiv of a 1 M solution of hexabutylditin in THF at 0 C under nitrogen, and the mixture is stirred for 20 min. The solution is cooled to — 78 °C and a solution of 1.5 mol equiv of diethylaluminum chloride in toluene is added. After stirring for 1 h at — 78 °C, a solution of 0.05 mol equiv of [tetrakis(triphenyl)phosphine]palladium(0) in THF is added followed by a solution of the allyl acetate in THF. The mixture is warmed to r.t., and stirred until the allyl acetate has reacted (TLC). The solution is cooled to 0°C, and an excess of aq ammonia slowly added. After an aqueous workup, the products arc isolated and purified by flash chromatography on silica gel using 1 % triethylamine in the solvent to avoid acid-induced loss of stannane. 

Phosphine palladium and phosphine platinum carbonyl cluster compounds. N. K. Eremenko, E. G. Mednikov and S. S. Kurasov, Russ. Chem. Rev. (Engl Transl.), 1985, 54, 394 (69). 

A mixture of l,4-dibromo-2,5-bis(3-sulfonatopropoxy)benzene 61 (0.78 g, 1.39 mmol), 60 (0.23 g, 1.39 mmol), Na2C03 (0.99 g) in doubly distilled water (47 mL), and DMF (20 mL) was heated at 85°C until the solids were completely dissolved. The resulting solution was cannulated to a 200-mL Schlenk flask with tris[(sulfonatophenyl)phosphine]palladium(0) (0.045 g) and the mixture was stined at 85°C for 10 h. The reaction mixture was concentrated to 25 mL by boiling and filtered. The filtrate was added dropwise to cold acetone (250 mL) to precipitate out the polymer. The polymer was collected by filtration, redissolved in a minimum of hot water, and reprecipitated by cooling. After repeating this procedure twice, the polymer was redissolved in distilled water and dialyzed for 72 h in 3500 gmol 1 cutoff membrane. After drying under vacuum, polymer 63 was obtained in 64% (0.42 g). 

It is possible to replace one isocyanide by triphenylphosphine, or to replace two isocyanides with diphos, giving phosphine analogues of these complexes. These species are not available from analogous reactions of phosphine-palladium(O) and (II) complexes. Reactions with active alkyl halides proceeds with oxidation nitric oxide also oxidizes these complexes. [Eqs. (31, 32)]. 

A bis(stannyl)bis(phosphine)palladium complex has a twisted square planar structure and shows facile unimolecular twist-rotation.170... 

Green used the cationic phosphine palladium hydride complex for the reaction of methanol (44). 

For example, cycloaddition of nitrone (643, R1 =Ph, R2 = Me) to DIO, catalyzed by chiral phosphine-palladium complexes (Fig. 2.42), gave isoxazolidines (644) in high yield with high enantioselectivity (794). 

It is worth noting, however, that chiral phosphine-palladium complexes generated from palladium salts and BINAP or MOP cannot be used for this oxidation because phosphines will be readily oxidized to phosphine oxides under the reaction conditions, leading to the deactivation of the catalyst. As reaction without the chiral catalyst will give a racemic product, this deactivation of the catalyst will cause a drop in the enantioselectivity of the whole process. 

The mechanistic suggestion depicted on Scheme 5.4 may be tme in an excess of phosphine ligands, and in fact, the [phosphine]/[palladium] ratio has a pronounced influence on the rate and selectivity of the reactions. However, it has also been demonstrated [20,58] that the palladium(It)-phosphine complexes used as catalyst precursors are reduced to Pd(0) in the... 

Practical hydroxycarbonylation of olefins is usually carried out with palladium catalysts and requires rather elevated temperatures. Pd/TPPTS [36-39], Pd/TPPMS [40] and Pd/sulfonated XANTHPHOS (51) were all applied for this purpose. In general, TOF-s of several hundred h can be observed under the conditions of Scheme 5.11, and with propene the concentration ratio of linear and branched acids is around l/b=1.3-1.4 [36,38]. At elevated temperatures and at low phosphine/palladium ratios precipitation of palladium black can be observed. It is known, that the highly reactive [Pd(TPPTS)3] forms easily under CO from a Pd(II) catalyst precursor and TPPTS [37], and that in the presence of acids it is in a fast equilibrium with [PdH(TPPTS)3] [39] ... 

Because of the relatively high loading of functional groups on these hyperbranched PE powders, it was feasible to characterize the products and intermediates in this catalysts synthesis by P CP-MAS NMR spectroscopy, ATR-IR spectroscopy, and XPS analysis. P CP-MAS NMR spectroscopy was especially useful for in distinguishing the phosphinated powder, phosphine-palladium complex, and any adventitiously formed phosphine oxide. Similar NMR analyses were not successfully carried out on hyperbranched grafts on PE films. However, when this same phosphine ligand synthesis and introduction of Pd was carried out on a PE film sample, it was possible to analyze... 

Pd bond in Me2Pd(dmpe) [dmpe=l,2-bis(dimethylphosphino)ethane] to generate phosphinate-palladium species with extrusion of a methane molecule (Scheme 40). Upon treatment the resulting palladium species with diphenylphosphine oxides, the remaining methyl-palladium bond was pro-tonated and a phosphinyl(phosphinato)palladium complex (20) was isolated. 

Methyl 5-fluoro-4-(trifluoromethylsulfonyloxy)-2,3-dihydro-l-methyl-7-0X0-1//,7//-pyrido[3,2,l-iy]cinnoline-8-carboxylate(68,R = Me,R = R = H, R = F, R = Me, R = CF3SO2O) was reacted with 3-tributylstannyl-2-cyclohexen-l-one in the presence of lithium chloride and bis(triphenyl-phosphine)palladium(II) chloride in tetrahydrofuran for 3 days to give a 4-(3-oxo-l-cyclohexen-l-yl)derivative (92EUP470578). 

Dimerization(46,47) with a palladium acetate/tertiary phosphine complex (di-ace tate-bis--[ tri-phenyl phosphine] palladium) in the absence of air gives primarily the desired linear dimer with smaller amount of branched, cyclic, and heavy product (Equation 13.). The reaction product is a complex mixture of cis and trans geometric isomers which makes analysis difficult. In order to simplify this problem, the product analysis is made after hydrogenation over 5% palladium on carbon. 

More recent review Hayashi, T. Asymmetric Grignard Cross-Coupling Catalyzed by Chiral Phosphine-Nickel and Phosphine-Palladium Complexes, in Asymmetric Reactions and Processes in Chemistry (Eliel, E. L., Otsuka, S. ed.), American Chemical Soc. Symp. Series Vol. 185, p. 177 (1982)... 

A more recent synthesis for (14-9) takes quite a different course. The first step comprises the displacement of one of the halogens in 1,4-dibromobenzene by the alkoxide from A-2-hydroxyethylpyrrolidine (15-2) in the presence of 18-crown ether to afford (15-3). Condensation of the lithium salt from (15-3) with 6-methoxy-tetralone (15-4) followed by dehydration of the initially formed carbinol give the intermediate (15-5), which incorporates the important basic ether. Reaction of that compound with pridinium bromide perbromide leads to the displacement of the vinylic proton by halogen and the formation of bromide (15-6). Condensation of that product with phenylboronic acid in the presence of a tetrakistriphenyl-phosphine palladium catalyst leads to the coupling of the phenyl group by the formal displacement of bromine. The product (14-9) is then taken on to lasoxifene (14-11) as above [16]. 

E)-1-Hexenyl iodide- 1-Hexene, 1-iodo-, (E)- (8,9) (16644-98-7) Tetrakis(triphenyl phosphine)palladium Palladium,... 

DIENES Copper I) bromidc-l)i-methyl sulfide. Tetrakis(triphenyl-phosphine)palladium. 

DIENES Bcn/.yldtlotobis(Iriphenyl-phosphine)palladium(ll). Copper(I) bromide-Dimethyl sulfide. Palladium(Il) chloride. Tetrakis(triphenyEphosphine)-palladium. Titanium IVichloride-Lithium aluminum hydride. 

LACTONES Bis(3-dimethylaminopro-pyDphenylphosphine. Copper(I) tri-fluoromethanesulfonate. Di-n-butyltin oxide. Dichlorobis(triphenyl-phosphine)-palladium. Ruthenium tetroxide. a-LACTONES lodosobenzene. 

Recently the use of allylic halide (see compound 96, Scheme 34) or sulfonate for the introduction of a malonyl residue at C-2 of pyranose derivatives using tetrakis(triphenyl-phosphine)palladium complex has been reported [132]. In this case, the malonyl chain is introduced anti to the leaving group at the 7-position. 

OTHER ORGANOMETALLIC REAGENTS (see also Carbonylation, Fluorination, Reformatsky reaction) with acids and acyl derivatives with acid halides Benzylchlorobis(triphenyl-phosphine)palladium(II), 30 Cadmium, 60... 

Diisobutylaluminum hydride-Boron trifluoride etherate, 116 Diphenylsilane-Palladium(II) chlo-ride-Triphenylphosphine, 126 Diphenylsilane-Tetrakis(triphenyl-phosphine)palladium(0)-Zinc chloride, 126... 

Diphenylsilane-Tetrakis(triphenyl-phosphine)palladium(0)-Zinc chloride, 126... 

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