反应详情

温度

80 °C

To a mixture of 5.6 g (0.03 mole) of thieno[3,4-d]isothiazol-3(2H)-one1,1-dioxide in 50 ml of dry pyridine is added 5.6 g (0.016 mole) of phosphorus pentasulfide portionwise over 3 minutes. The viscous mixture is slowly heated in an oil bath under an atmosphere of nitrogen. The temperature of the oil bath is slowly increased to 80° C. after 30 minutes. The temperature of the oil bath is then kept at 80° C. for 25 minutes, the internal temperature reading 63° C. The solution is cooled to 50° C. and is added dropwise over 5 minutes to 200 ml of water and cooled in an ice bath. The precipitate which forms is collected and discarded. The filtrate is cooled in ice and acidified with concentrated hydrochloric acid to pH 1. The precipitate which forms is collected to yield 40% of material. In another experiment, a sample is recrystallized from water to obtain an analytical sample, m.p. 196°-8° C. (dec.).

1. temperatureThe viscous mixture is slowly heated in an oil bath under an atmosphere of nitrogen
2. customreading 63° C
3. temperatureThe solution is cooled to 50° C.
4. temperaturecooled in an ice bath
5. customThe precipitate which forms is collected
6. temperatureThe filtrate is cooled in ice
7. customThe precipitate which forms is collected