Acetic Acid → 7-(1-Cyclopropylmethyl-piperidin-4-yloxy)-3,4-dihydro-2H-2,4a,5-triaza-fluoren-1-one

Participants

Reaction Conditions

Reaction Steps

To a solution of 0.40 g (1.40 mmol) 7-(piperidin-4-yloxy)-3,4-dihydro-2H-2,4a,5-triaza-fluoren-1-one in 8 mL tetrahydrofuran, 30 μL (30 μg, 1.67 mmol) water, 0.16 mL (0.15 g, 2.11 mmol) cyclopropanecarboxaldehyde, 0.24 mL (0.25 g, 4.2 mmol) acetic acid and 2.1 mL (1.93 g, 2.1 mmol) sodium cyanoborohydride (1M solution in tetrahydrofuran) were added successively and the reaction mixture was stirred for 18 hours at 55° C. After cooling to room temperature the reaction was poured on 10% aqueous sodium bicarbonate solution and was extracted three times with ethyl acetate. The combined organic layers were washed with brine, dried over magnesium sulfate, filtered and evaporated. The residue was flash-chromatographed on silica gel with dichloromethane:methanol:ammonia (9:1:0.1 v/v) as eluant to give 0.19 g (40%) of the desired compound as a white solid.

Provenance & Evidence