Acetic Acid → Diisopropyl Ether

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Reaction Steps

The procedure used in Example 216 is followed. In a 20 ml round-bottomed flask under an argon atmosphere, dissolve 303 mg of 4-{5-[2-(pyrrolidin-1-yl)ethylaminocarbonyl]-1H-benzimidazol-2-yl}-9H -fluoren-9-one oxime (Z,E), obtained in the previous stage, in a mixture of 1.5 ml of ethanol and 1.5 ml of water and 1.5 ml of acetic acid, at room temperature. Add 175 mg of zinc in three stages, and, between each addition, stir for approximately one hour to two hours. Add Celite and filter. The filtrate is concentrated under reduced pressure. After purification by flash chromatography on silica gel (40-63 μm), eluting with a mixture of dichloromethane and ammonia as a 7N solution in methanol (9/1 by volume) and then formation of a paste with diisopropyl ether, in this way we obtain 257 mg of 4-{5-[2-(pyrrolidin-1-yl)ethylaminocarbonyl]-1H-benzimidazol-2-yl}-9H-fluorene-9(R,S)-amine, in the form of a beige solid, which is used as it is in the following stage, with the following characteristics:

Provenance & Evidence