The application belongs to the technical field of organic compounds, and particularly relates to a preparation method of 3-[3-(dimethylamino)methyl-1-cyclohexen-2-yl]
phenol hydrochloride and isomers thereof. The preparation method comprises the following steps: heating and reacting compound III with an acid, then adding
sodium hydroxide to adjust the pH value to be alkaline; then continuously adding an extractant to extract, separating to obtain a
water layer, introducing
carbon dioxide into the
water layer, and precipitating white solids in the
water layer; filtering to obtain a mixture of compound VI and compound VII; dissolving the mixture of compound VI and compound VII in a polar
organic solvent, introducing
hydrogen chloride gas, and performing
crystallization and
filtration to obtain compound I; and concentrating, filtering and recrystallizing the
mother liquor to obtain compound II. The application simplifies the preparation process of
tramadol analogs and integrates the process into two-step reactions; the molecular structure of
tramadol hydrochloride is designed to optimize the existing problems of individual differences in
analgesic effect and side effects of original
tramadol and analogs.