在有机合成中常见的钯催化偶联反应有：Suzuki-Miyaura偶联, Stille偶联, Negishi偶联, Kumada偶联, Hiyama偶联, Sonogashira偶联, Heck反应, Buchwald-Hartwig反应等等。因此常见的钯催化剂应用非常广泛，虽然这些催化剂都已商业化，但对于大规模生产的反应，可以自己制备降低成本。

Pd(PPh3)4的制备

A mixture of palladium dichloride (17.72 g., 0.10 mole), triphenylphosphine (131 g, 0.50 mole), and 1200 ml of dimethyl sulfoxide is placed in a single-necked, 2L, round-bottomed flask equipped with a magnetic stirring bar and a dual-outlet adapter. A rubber septum and a vacuum-nitrogen system are connected to the outlets, The system is then placed under nitrogen with provision made for pressure relief through a mercury bubbler. The yellow mixture is heated by means of an oil bath with stirring until complete solution occurs (ca. 140 ℃). The bath is then taken away, and the solution is rapidly stirred for approximately 15minutes. Hydrazine hydrate (20 g, 0.40 mole) is then rapidly added over approximately 1 minute from a hypodermic syringe. A vigorous reaction takes place with evolution of nitrogen. The dark solution is then immediately cooled with a water bath; crystallization begins to occur at ca. 125℃. At this point the mixture is allowed to cool without external cooling. After the mixture has reached room temperature it is filtered under nitrogen on a coarse, sintered-glass funnel. The solid is washed successively with two 50 ml. portions of ethanol and two 50 ml portions of ether. The product is dried by passing a slow stream of nitrogen through the funnel overnight. The resulting yellow crystalline product weighs 103.5-108.5 g. (90-94% yield).A melting point determination on a sample in a sealed capillary tube under nitrogen gave a decomposition point of 116℃ (uncorrected). This compares with a similar determination(115℃) performed on the product prepared by the method of Malatesta and Angoletta.

Properties:

The Pd(PPh3)4 complex obtained by this procedure is a yellow, crystalline material possessing moderate solubilities in benzene (50 g/L), methylene chloride, and chloroform.The compound is less soluble in acetone, tetrahydrofuran and acetonitrile. Saturated hydrocarbon solvents give no evidence of solution. Although the complex may be handled in air, it is best stored under nitrogen to ensure its purity.

Pd(PPh3)2Cl2的制备

将PdCl2 (50 g, 0.284 mol)和PPh3 (162.5 g, 0.62 mol) 加入苯腈（150 mL）中，氮气置换三次，升温到200℃，反应30 分钟，降温至室温析出晶体，滤出固体，用乙醚洗涤，抽干，得到产品（362 g, 95.8 %）。

Pd(dppf)Cl2的制备

To absolute acetonitrile (1950 mL) degassed via three vacuum/nitrogen ingress cycle was added dichloropalladium (13 g, 73 mmol), the mixture was refluxed at 90~100 °C overnight. The reactant was concentrated to obtain Pd(CH3CN)2Cl2 as orange solid. To a suspension of Pd(CH3CN)2Cl2 (19 g, 73 mmol) in benzene (680 mL) was added a solution of dppf (40.6 g,73 mmol) in benzene (680 mL), the mixture was stirred at rt overnight, the reddish brown precipitate formed was collected by filtration, washed with benzene, and dried in vacuo to give Pd(dppf)2Cl2 (~48 g) in over 90% yield. This is pure enough for the next step, the complex can be recrystallized from chloroform/benzene.

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