In a 2L three-necked flask with magnetic stirring, add 2-nitropropane, ethanol, concentrated sulfuric acid dissolved in aqueous solution, stirring reaction at 20 ~ 25 for 48 h. Distill under reduced pressure, concentrate to remove ethanol, concentrate the residue by adding 450 mL of water and 500 mL of ethyl acetate extraction, stand, separate the organic phase, the aqueous phase and then 500 mL of ethyl acetate extraction once, the combination of the organic phase, distillation under reduced pressure, concentrate the organic phase, remove ethyl acetate. Remove ethyl acetate. The aqueous phase was adjusted by adding 45% aqueous sodium hydroxide solution to adjust the pH value of about 8, adding ethyl acetate 500mL extraction twice, standing, separated from the organic phase, anhydrous sodium sulfate drying, filtration, filtrate under reduced pressure distillation to remove ethyl acetate, concentrated residue for the yellowish oily, in a 1L three-necked flask with magnetic stirring and constant-pressure dropping funnel, 20-25 , add 30% hydrogen chloride dropwise - ethanol solution 75.0.0, and concentrated. -Ethanol solution 75.0g, 30min after dropping, continue to keep warm 20 ~ 25 stirring for 30min, 20 ~ 25 drop 250mL anhydrous ether, slowly precipitate white crystals, continue to keep warm to crystallize 4h, filtration, 45 drying under reduced pressure for 8h, get white crystals.
