(Diethylamino)sulfur trifluoride → (4R,9aR)-6-Fluoromethyl-4-methyl-3,4,9,9a-tetrahydro-1H-2,4a,5-triaza-fluorene-2-carboxylic acid tert-butyl ester

Beteiligte Stoffe

Reaktionsschritte

A solution of 82.0 μl (0.11 g, 0.63 mmol) diethylaminosulphur trifluoride in 2 ml dichloromethane was cooled to −78 deg C. and treated with a solution of 0.20 g (0.63 mmol) (4R,9aR)-6-(2-hydroxy-ethoxymethyl)-4-methyl-3,4,9,9a-tetrahydro-1H-2,4a,5-triaza-fluorene-2-carboxylic acid tert-butyl ester (Example 15, intermediate b) in 2 ml dichloromethane. The cooling bath was removed and the reaction stirred for 1 h at room temperature. The solution was extracted with 10% aqueous sodium bicarbonate solution, washed with brine, dried over magnesium sulfate, filtered and evaporated. The residue was chromatographed on silica gel (0.032–0.063 mm) with ethyl acetate:n-hexane (1:2) as eluant to afford the desired compound as a colorless oil (51.7%).

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