Hydrochloric Acid → Tetrahydro-3-methyl-2-(nitromethylene)-1,3-thiazine

Participants

Reaction Conditions

Reaction Steps

Into 40 ml of methanol were added 5.0 g of 1-methylamino-3-propanethiol and 0.8 g of caustic soda, followed by stirring, to be completely dissolved therein. Then, the mixture was cooled to 0° C. While stirring the solution, a solution of 1.6 g of caustic soda dissolved in 25 ml of methanol and a solution of 2.8 g of 2,2-dichloronitroethylene diluted in 20 ml of methanol were added at the same time dropwise slowly over 50 minutes, and the reaction was carried out for one hour at about 8° C. After the reaction, the reaction mixture was neutralized to pH 7 with 3 N aqueous hydrochloric acid, and then with addition of 60 ml of water, extraction with 50 ml of methylene chloride was repeated four times. The extracts were concentrated to give 3.38 g of tetrahydro-3-methyl-2-(nitromethylene)-1,3-thiazine (yield: 97%).

Provenance & Evidence