under appropriate reaction conditions accordingly a method for preparing the iridium complex includes the following steps 1 reacting a 1 phenylisoquinoline based compound or 2 phenylpyridine based compound with an iridium source under heating to form an intermediate and 2 mixing the phenylsilyl phosphine compound an alcohol and the intermediate followed by reacting in the presence of a catalyst under heating so as to obtain the iridium complex preferably the 1 phenylisoquinoline based compound is 1 phenylisoquinoline and the 2 phenylpyridine based compound is 2 4 6 difluorophenyl pyridine or 2 phenylpyridine preferably the iridium source is iridium iii chloride hydrate ircl 3 h 2 o the alcohol is used to provide the oxygen atom bonding si and ir in the iridium complex since the step 2 is conducted at high temperature boiling point of the alcohol needs to be sufficiently high preferably the alcohol is 2 methyloxyethanol preferably the catalyst is sodium carbonate potassium acetate or sodium acetate 0 10 gram 0 087 mmole of pd pph 3 4 was placed in a 100 ml two neck bottle followed by adding 3 7 grams 20 mmoles of diphenyl phosphine toluene 3 1 ml 22 mmoles of triethylamine and 2 6 ml 20 mmoles of 1 bromo 2 iodo benzene into the two neck bottle in nitrogen atmosphere to obtain a mixture the mixture.