The invention discloses a method for synthesizing an important intermediate 4-amino-3-(4-phenoxy-phenyl)-1H-pyrazolo[3,4-d]
pyrimidine of
Ibrutinib. The method comprises the following steps: step one, condensing
malononitrile and
triethyl orthoformate and then carrying out a one-pot reaction with hydrazine
hydrate to obtain 5-amino-4-cyano-
pyrazole; step two, condensing the 5-amino-4-cyano-
pyrazole with
formamide to prepare a compound of formula (II) 4-amino-1H-pyrazolo[3,4-d]
pyrimidine; step three, carrying out a bromination reaction of the compound of formula (II) and brominating agent to obtain a compound of formula (III) 4-amino-3-
bromine-1H-pyrazolo[3,4-d]
pyrimidine; step four, carrying out a Stille reaction on the compound of formula (III) and trimethyl p-phenoxy phenyltin under the catalyst effect of
metal palladium to prepare a compound of formula (I) 4-amino-3-(4-phenoxy-phenyl)-1H-pyrazolo[3,4-d]pyrimidine. According to the method for synthesizing the important intermediate 4-amino-3-(4-phenoxy-phenyl)-1H-pyrazolo[3,4-d]pyrimidine of
Ibrutinib provided by the invention, raw materials are low in price and easily obtained, the
reaction conditions are moderate, the operation is simple and convenient, the method is suitable for industrial production, and a new way is provided for preparing
Ibrutinib and intermediate.