Hydrochloric Acid → 2-nitromethylenetetrahydro-2H-1,3-thiazine

Temperature

0 °C

Into 40 ml of methanol were added 5.5 g of 1-amino-3-propanethiol and 2.4 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 2.8 g of 2,2-dichloronitroethylene diluted in 10 ml of methanol was added dropwise slowly over 15 minutes, and the reaction was carried out for one hour. The reaction was exothermic and the liquid temperature was maintained at lower than 10° C. (about 8° C.) After the reaction, the reaction mixture was neutralized to pH 7 with 6 N aqueous hydrochloric acid, and then with addition of 30 ml of water, extraction with 50 ml of chloroform was repeated four times. The extracts were concentrated to give 2.24 g of tetrahydro-2-(nitromethylene)-1,3-thiazine (yield: 70.0%).

1. dissolutionto be completely dissolved
2. stirringWhile stirring the solution
3. additionwas added dropwise slowly over 15 minutes
4. temperaturethe liquid temperature was maintained at lower than 10° C. (about 8° C.)
5. customAfter the reaction
6. concentrationThe extracts were concentrated

ORD record

ord-807ebc9403cc40b8ba34883f6797b256

Source dataset

uspto-grants-1987_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04665172