Preparation of 1,1′-bis(diphenylphosphino)ferrocene palladium dichloride II_Kain Industrial Additive

Overview^[1]

1,1'-Bis(diphenylphosphino)ferrocene palladium dichloride II is widely used as a catalyst in the fields of organic chemistry, pharmaceutical chemistry and liquid crystal material synthesis. At present, its main synthesis methods are: 1) reaction method between palladium chloride (K, Na, Li salt) and dppf, 2) palladium chloride and acetonitrile (benzonitrile) complex and dppf ligand exchange method. Method 1 utilizes the reaction of palladium chloride and sodium chloride (potassium chloride or lithium chloride) to obtain highly soluble chloropalladate, and then prepares 1,1'-bis(diphenylphosphino)ferrocene dichloride Palladium II, although this method shortens the reaction time and improves the reaction yield, the post-processing is cumbersome and it is easy to introduce K, Na, Li and other impurity ions, resulting in low quality catalyst; the acetonitrile and benzonitrile used in method 2 are both It is an extremely toxic chemical, and this method requires a long reaction time and low efficiency.

Preparation^[1]

A method for preparing 1,1'-bis(diphenylphosphino)ferrocene palladium dichloride II (dppfPdCl2), including the following steps:

(a) Add palladium chloride to concentrated hydrochloric acid and heat to 40-80°C to dissolve. The amount of hydrochloric acid used is 0.2-1.0 times the mass of palladium chloride. Add ethanol to dilute it. The amount of ethanol used is 10 times the mass of palladium chloride. -50 times;

(b) Add 3.0-5.0 times the mass of palladium chloride of bisdiphenylphosphinoferrocene (dppf) into the tetrahydrofuran solution and heat to 40-80°C until dissolved. The amount of tetrahydrofuran used is palladium chloride. 20-30 times the mass;

(c) Add the solution obtained in step (a) dropwise to the solution obtained in step (b). After the addition is completed, keep it at 45-80°C for 0.5-3h, then cool, filter, wash, and dry in vacuum. Red crystals of 1,1'-bis(diphenylphosphino)ferrocene palladium II chloride were obtained.