Acetals dichlorobis palladium

Cross-coupling of two vinyl groups Dichlorobis(triphenylphosphine)pal-ladium(II), 103 Palladium(II) acetate, 232 Tetrakis(triphenylphosphine)palla-dium(0), 289... 

Dichlorobis(triphenylphosphine)-palladium(II), 103 Methyl (trifluoromethylsulfonyl)-methyl sulfone, 193 Nickel carbonyl, 198 Palladium(II) acetate, 232... 

A flask was charged with 2,7-dibromofluorene (17.73 mmol), bis(pinacolato)dibor-on (44.33 mmol), potassium acetate (5.22 g, 53.20 mmol), dichlorobis(tricyclohex-ylphosphine)-palladium(II) (0.61 mmol), and 150 ml of 1,4-dioxane and stirred at 100°C for 24 hours. The reaction mixture was quenched with 100 ml of water and extracted twice with 200 ml of CCI3H. Combined extracts were washed with 100 ml of water, dried with Na2S04, and concentrated. The residue was purified by column chromatography using CH2CI2, and the product was isolated as a white solid in 76% yield. 

A round-bottom flask was charged with a mixture of 2,6-dimethylphenyl trifluoromethanesulfonate (127.1 mg, 0.5 mmol), anhydrous lithium chloride (4 mmol), copper(I) bromide (0.2 mmol), and dichlorobis(triphenylphosphine)-palladium(II) (10-20 mol %) suspended in DMF (2.5 cm ). 2-Methoxyphenyl-tributyltin (1-1.5 mmol) was added to the mixture in two portions, i.e., at the beginning of the reaction and at half completion. A crystal of 2,6-bis(l,l-dime-thylethyl)-4-methylphenol (BHT) was added as an inhibitor of radical processes, and the mixture was then heated to reflux, under argon, during 8 - 24 h. Water and Et20 (25 cm ) was added, and the organic phase was washed subsequently with hydrochloric acid solution (1.5 mol dm , 6 x 20 cm ), a saturated solution of potassium fluoride (5 x 20 cm ), and finally dried over anhydrous sodium sulfate. Evaporation to dryness furnished a residue and that was suspended in ethyl acetate and the insoluble material was filtered off. The filtrate was... 

Solvent effects on, and products from, reaction of styrene with ethylene in the presence of di-)ti-chloro-dichlorobis(styrene)dipalladium(n), [Pd-(Ph CH—CH2)Cl2]2, indicate a mechanism similar to (i)->(iv) above, with the addition of a preliminary equilibrium between the dimer and solvated monomers. The mechanism of reaction of styrene with vinyl compounds, catalysed by the same chloride-bridged dipalladium complex, has been studied using isotopic tracer (H, D) experiments. Palladium-acetate-catalysed reaction of styrene with benzene, also investigated using deuterium tracer experiments, involves no hydride shift, in contrast to the rather closely related Wacker process. The importance of intermediates with palladium-carbon n-bonds in palladium(ii)-catalysed alkylation and arylation of alkenes has been demonstrated. 

The controlled-potential electrolyses were carried out in a cell with three separated compartments. The cathode was a reticulated carbon rod and the anode was a platinum wire. As reference electrode was used a modified SCE. The catholyte was prepared by dissolving 2-aminophenol in CH3CN, containing n-Bu NBF (0.2M) as well as an excess of base and dichlorobis(triphenylphosphine) palladium(II) or palladium(II) acetate as catalyst. Carbon monoxide was bubbled through a glass capillary into the cathodic solution that subsequently was kept under a CO pressure of 1 atm. The electrolyses were interrupted when the current dropped to the value of the background current. 

---