4-[4-(4-ethoxy-2-fluoro-phenoxy)-pyrazolo[3,4-d]pyrimidin-1-yl]-piperidine-1-carboxylic acid tert-butyl ester   、                                                                                      trifluoracetic acid-dichloromethane                                                                                                                                                                                                                                                                      反应 3.0h,
                                                                                                                以to afford 4-(4-ethoxy-2-fluoro-phenoxy)-1-piperidin-4-yl-1H-pyrazolo[3,4-d]pyrimidine trifluoroacetate salt (112 mg, 99%) which的产率得到4-(4-ethoxy-2-fluoro-phenoxy)-1-piperidin-4-yl-1H-pyrazolo[3,4-d]pyrimidine trifluoroacetate