Carbonyl compounds palladium chloride catalysts

The oxidation of olefins to carbonyl compounds by means of palladium chloride catalysts (and involving intermediate organopalladium compounds) 22, 225, 226),... 

Palladium catalysts, 10 42 14 49 16 250 Palladium-catalyzed carbonylation, 13 656 Palladium chloride/copper chloride, supported catalyst, 5 329 Palladium compounds, 19 650-654 synthesis of, 19 652 uses for, 19 653-654 Palladium films, 19 654 Palladium membranes, 15 813 Palladium monoxide, 19 651 Palladium oxide, 19 601... 

Additional examples of palladium-catalyzed cross-couplings, in particular with allenylzinc compounds, can be found elsewhere [11, 15, 36]. A systematic study comparing several chiral palladium phosphine catalysts in the reaction of 4,4-di-methyl-1,2-pentadienylzinc chloride and iodobenzene revealed that an enantiomeric excess of only 25% was obtained from the best catalyst combination PdCl2 and (R,R)-DIOP [15]. The synthetic value of these transformations of donor-substituted allenes as precursors is documented by the preparation of a/l-unsaturatcd carbonyl... 

Alkyne cyclotrimerization occurs at various homogeneous and heterogeneous transition metal and Ziegler-type catalysts [7], Substituted benzenes have been prepared in the presence of iron, cobalt, and nickel carbonyls [8] as well as trialkyl- and triarylchromium compounds [9]. Bis(acrylonitrile)nickel [10] and bis(benzonitrile)palladium chloride [11] catalyze the cyclotrimerization of tolane to hexaphenylbenzene. NiCl2 reduced by NaBH4 has been utilized for the trimer-ization of 3-hexyne to hexaethylbenzene [12]. Ta2Cl6(tetrahydrothiophene)3 and Nb2Cl6(tetrahydrothiophene)3 as well as 7 -Ind-, and 77 -Ru-rhodium... 

Nickel, palladium and copper catalysts can effect a variety of C — C bond-forming reactions P to the ester carbonyl via j8-zinc esters. These include 1,4-addition to a,jS-unsaturated carbonyl compounds (copper), arylation with aryl halides (palladium, nickel), allylation with allyl chloride (copper), and acylation with acyl chlorides (palladium, copper). " ... 

The palladium chloride reacts with olefins in a different course if water is present. Carbonyl compounds rather than chlorides are formed. The reaction with ethylene produces acetaldehyde and it can be done catalyticaUy in the presence of oxygen and cupric chloride, which is known as the Wacker process. The process is one of the most important commercially useful reactions employing transition metal catalysts. ... 

Apart from routine applications to cyclopropane synthesis,the application of new catalysts to the decomposition of diazo-compounds has received considerable attention. The use of palladium acetate, originally reported in 1972 by Paulissen et o/., has been extended and applied to diazomethane and ethyl diazoacetate in the presence of aP-unsaturated carbonyl compounds. With a- and a-substituted aP-unsaturated ketones, stereospecific cis-addition occurs in excellent yields, but the catalyst proves to be ineffective with analogous trisubstituted olefins, as illustrated for the formation of (110) with diazomethane. The use of palladium chloride with the... 

Aromatic aldehydes and ketones are reduced to the corresponding hydrocarbons in good yield by catalytic transfer reduction using cyclohexene or limonene as a donor, palladium-carbon as catalyst and a Lewis-acid promotor such as ferric chloride. The major competing reaction is decarbonylation, otherwise the reaction is straightforward and simply involves heating the catalyst, carbonyl compound, and donor under reflux for 3—5 h, furthermore the method is convenient and dispenses with elaborate equipment or potentially explosive hydro n. ... 

The oxidative carbonylation of arenes to aromatic acids is a useful reaction which can be performed in the presence of Wacker-type palladium catalysts (equation 176). The stoichiometric reaction of Pd(OAc)2 with various aromatic compounds such as benzene, toluene or anisole at 100 °C in the presence of CO gives aromatic acids in low to fair yields.446 This reaction is thought to proceed via CO insertion between a palladium-carbon (arene) allyl chloride, but substantial amounts of phenol and coupling by-products are formed.447... 

Unsaturated compounds have been carbonylated by their reaction with carbon monoxide under pressure in the presence of palladous chloride, but supported palladium catalysts will also perform this function (15). This is perhaps the clearest illustration of a class of reactions which proceeds both homogeneously and heterogeneously with apparent comparable facility. 

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