Methyl morpholine oxide → Pnu-288034

Beteiligte Stoffe

Reaktionsschritte

N-({(5S)-3-[3,5-difluoro-4-(4-thiomorpholinyl)phenyl]-2-oxo-1,3-oxazolidin-5-yl}methyl)acetamide (13.36 g, 35.97 mmol) is dissolved in a solution of 25% water/acetone and then treated sequentially with 4-Methylmorpholine N-oxide (3 eq, 12.64 g, 107.91 mmol) and a catalytic amount of osmium tetroxide (2.8 mL). The reaction is stirred overnight at room temperature under nitrogen. In the morning, another 2 mL of osmium tetroxide is added. Another 2 eq of 4-Methylmorpholine N-oxide and 2.5 mL of osmium tetroxide are added a few hours later. The reaction is stirred overnight again under nitrogen. The following morning, the reaction is complete. The reaction mixture is quenched with a solution of sodium hydrosulfite and then extracted with methylene chloride three times. The organic layer is washed with sodium hydrosulfite and brine, dried with sodium sulfate, filtered, and concentrated. The crude product is then chomatographed on silica gel, eluting with methylene chloride and then 2% and 5% methanol/methylene chloride solutions. Appropriate fractions are combined and concentrated to yield 11.99 g (83%) of the title compound as a white solid, mp: 187-189.5° C.

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