Isothipendyl

PreparationThe industrial production method of ISOTHIPENDYL technical grade is carried out according to the following steps: Under nitrogen protection, 100 kg of anhydrous acetonitrile is pumped from an acetonitrile storage tank into a 300 L reactor via a metering pump. 20 kg of 1-hexaazine phenothiazine and 2.4 kg of sodium hydride are added through the feed port. After reacting the materials at 30°C for 1 hour, the steam valve is opened, and steam is introduced into the reactor jacket for reflux reaction for 2 hours. Then, 26.5 kg of 1-p-toluenesulfonyl-2-N,N-dimethylpropylamine is added through the feed port, and the reaction is refluxed for 3 hours. After the materials are cooled to 30°C, insoluble matter is filtered out through a filtration system, and the acetonitrile mother liquor is returned to the reactor from the storage tank. Hydrogen chloride is bubbled into the acetonitrile mother liquor through a vaporizer, buffer tank, and flow meter. White crystals precipitate in the system. HPLC monitoring continues until ISOTHIPENDYL disappears from the mother liquor, at which point the reaction is stopped. The above materials were centrifuged, washed with frozen ethanol, centrifuged again, and dried to obtain 24.1 kg of ISOTHIPENDYL hydrochloride. Acetonitrile was recovered by distillation of the centrifugal mother liquor, and the residual liquid in the reactor was treated and discharged. 70 kg of water was pumped into a 300 L reactor via a metering pump, and the above ISOTHIPENDYL hydrochloride was added through the feed port. The mixture was mechanically stirred until completely dissolved. A 30 wt% NaOH solution was injected into the reactor from a high-level tank via a flow meter. The pH of the system was adjusted to 8, and stirring was continued for 0.5 h before the reaction was stopped. The material was centrifuged and vacuum dried to obtain 20.2 kg of ISOTHIPENDYL with a purity of 99.2% (HPLC) and a yield of 71%.