1,4-Dioxane → (S)-3,5-dichloro-4-(2-(3-(cyclopropylmethoxy)-4-(difluoromethoxy)phenyl)-2-(2-(3-(cyclopropylmethoxy)-4-(methylsulfonamido)-benzoyloxy)acetoxy)ethyl)pyridine 1-oxide

Participants

Reaction Steps

To a solution of (S)-4-(2-(2-(4-(N-(tert-butoxycarbonyl)methylsulfonamido)-3-(cyclopropylmethoxy)benzoyloxy)acetoxy)-2-(3-(cyclopropylmethoxy)-4-(difluoromethoxy)phenyl)ethyl)-3,5-dichloropyridine 1-oxide (2.457 g, 2.91 mmol) in dry DCM (85 ml), HCl 4M in dioxane (7.26 ml, 29.1 mmol) was added, and the reaction was stirred at RT overnight. Then the solvent was evaporated and the residue was purified by flash chromatography on silica gel (eluent: DCM/MeOH 99:1). Combined fractions were evaporated and the resulting solid was triturated with EtOH/MeOH 95:5 to afford (S)-3,5-dichloro-4-(2-(3-(cyclopropylmethoxy)-4-(difluoromethoxy)phenyl)-2-(2-(3-(cyclopropylmethoxy)-4-(methylsulfonamido)-benzoyloxy)acetoxy)ethyl)pyridine 1-oxide as a white solid (1.761 g, 2.362 mmol, 81% yield, MS/ESI+ 745.13 [MH]+, [αD]=−34.69, c=0.49, DCM).

Provenance & Evidence