CON(C)[C:4](=[O:24])[C:5]1[CH:10]=[C:9]([S:11]([F:16])([F:15])([F:14])([F:13])[F:12])[CH:8]=[C:7]([NH:17][C:18](=[O:23])[C:19]([F:22])([F:21])[F:20])[CH:6]=1.[CH3:26][Si](C)(C)N[Si](C)(C)C.[Li].C[Mg]Br.Cl>C1COCC1.C(OCC)(=O)C.O>[C:4]([C:5]1[CH:6]=[C:7]([NH:17][C:18](=[O:23])[C:19]([F:20])([F:22])[F:21])[CH:8]=[C:9]([S:11]([F:15])([F:13])([F:14])([F:12])[F:16])[CH:10]=1)(=[O:24])[CH3:26]
N-Methoxy-N-methyl-5-pentafluorosulfanyl-3-(2,2,2-trifluoroacetylamino)benzamide (20 mg) was dissolved in absolute THF (2 ml) and stirred at RT with lithium hexamethyldisilazane solution (45 μl, 1 M in THF) for 30 min. Methylmagnesium bromide solution (17 μl, 3 M in diethyl ether) was then added dropwise with stirring at 0° C. After stirring at RT for 1 h, 1N hydrochloric acid was added dropwise with cooling, followed by water and ethyl acetate. The organic phase was separated off and the water phase was additionally extracted twice with ethyl acetate. The combined ethyl acetate phases were dried over magnesium sulfate, filtered and concentrated. 17 mg of crude product were obtained. After further N-methoxy-N-methyl-5-pentafluorosulfanyl-3-(2,2,2-trifluoroacetylamino)benzamide (60 mg) was reacted in the manner described (crude product obtained: 60 mg), the crude products were combined and 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 three times with ethyl acetate. The combined extracts were dried over magnesium sulfate, filtered and concentrated. 37 mg of the desired compound were obtained.
Loading…
