Production process of isotretinoin

The invention relates to the technical field of pharmacy, and particularly discloses a production process of isotretinoin. The invention relates to an isotretinoin production process, which comprises: stirring and mixing tetrahydrofuran, magnesium powder and bromoethane, introducing vinyl chloride, cooling, dropwise adding ionone, adding into an ammonium chloride saturated solution, layering, carrying out reduced pressure recovery, and carrying out vacuum distillation to obtain enol; the method comprises the following steps: stirring and mixing methanol and pyridine, dropwise adding hydrochloric acid, then adding enol and triphenylphosphine, heating and refluxing, concentrating into paste, cooling, firstly adding a potassium hydroxide isopropanol solution, then dropwise adding an isopropanol ring solution, carrying out heat preservation reaction, adding into water, adjusting the pH value to be 1, adding petroleum ether for extraction, and carrying out reduced pressure recovery to obtain mixed acid; adding eth