反应详情

3-Amino-5-pentafluorosulfanylbenzoic acid (200 mg, Example 11a) was dissolved in methylene chloride (12 ml). The following were added successively with stirring: N,O-dimethylhydroxylamine×HCl (148 mg), 1-propanephosphoric anhydride (242 mg) and triethylamine (292 μl). The clear solution was stirred at RT for 4 h and allowed to stand over the weekend. For work-up, the reaction mixture was concentrated, and the residue was taken up in ethyl acetate and extracted twice with potassium hydrogensulfate solution. After the ethyl acetate phase had subsequently been extracted twice with sodium carbonate solution, it was dried over magnesium sulfate, filtered and concentrated. The crude product obtained was purified by means of preparative chromatography. The product-containing fractions were combined, freed from the acetonitrile, rendered basic with saturated sodium hydrogencarbonate solution and extracted with ethyl acetate three times. The combined extracts were dried over magnesium sulfate, filtered and concentrated. 77 mg of the desired compound were obtained.

1. additionThe following were added successively
2. stirringThe clear solution was stirred at RT for 4 h
3. concentrationFor work-up, the reaction mixture was concentrated
4. extractionextracted twice with potassium hydrogensulfate solution
5. extractionAfter the ethyl acetate phase had subsequently been extracted twice with sodium carbonate solution, it
6. dry with materialwas dried over magnesium sulfate
7. filtrationfiltered
8. concentrationconcentrated
9. customThe crude product obtained
10. customwas purified by means of preparative chromatography
11. extractionextracted with ethyl acetate three times
12. dry with materialThe combined extracts were dried over magnesium sulfate
13. filtrationfiltered
14. concentrationconcentrated