反应详情

温度

-50 °C

To a batch of 1-lithiophenoxathiin 10,10-dioxide, prepared according to the procedure of Example 1B from 44 g of phenoxathiin 10,10-dioxide chilled to ≤-50° C. in a dry ice/acetone bath, was slowly added chilled acetaldehyde (20.37 g). The reaction mixture was maintained at -50° C. during the addition which took 45 min. It was then allowed to warm to room temperature, and the solvent was removed under reduced pressure. The yellow-orange residue was stirred overnight with 0.5 N hydrochloric acid (259 mL), filtered and washed with water (500 mL). It was then washed throughly with ethanol (1.5 L), filtered and dried to give 1-(1-hydroxyethyl) phenoxathiin 10,10-dioxide (41 g) which was sufficiently pure for the next step (conversion to 1-ethylphenoxathiin 10,10-dioxide).

1. temperaturechilled to ≤-50° C. in a dry ice/acetone bath
2. additionwas slowly added
3. temperatureto warm to room temperature
4. customthe solvent was removed under reduced pressure
5. filtrationfiltered
6. washwashed with water (500 mL)
7. washIt was then washed throughly with ethanol (1.5 L)
8. filtrationfiltered
9. customdried