Preparation method of apixaban intermediate suitable for industrial production

The invention discloses a synthesis method of an apixaban intermediate suitable for industrial production. The method comprises the following steps: carrying out phase-transfer catalytic amidation reaction on paranitroaniline and 5-chlorovaleryl chloride in an organic phase and water phase two-phase system under an inorganic weakly alkaline condition to obtain an APM01 solution, and adding a sodium hydroxide water solution, and cyclizing in a pot to obtain an APM02 solution; directly carrying out alpha-reactive hydrogen dichlorination on an APM02 organic solution and phosphorus pentachloride after simple acid pickling, liquid separation and drying to obtain an APM03 solution; carrying out condensation-elimination reaction on the APM03 solution and excessive morpholine after simple acid pickling and liquid separation, and carrying out simple crystallization and purification treatment to separate out an APM04 solid, and reducing the APM04 into APM05 by sodium sulfide; and carrying out amidation-cyclization two-