Diethylamine → 4-acetyl-2,3,4,5-tetrahydro-1H-1,4-benzodiazepin-1-ylamine

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Reaction Steps

4-Acetylbenzodiazepine (28.5 g, 50.15 m) and allyl N-[(mesitylsulfonyl)-oxy]carbamate (53.8 g, 0.18 m) were combined in toluene (270 mL) and heated under reflux for 2.5 h. The reaction was quenched with 0.5 N NaOH. The precipitate that formed was removed by filtration and the aqueous filtrate was extracted with ethyl acetate (3×). The combined organic layers were washed with saturated sodium chloride solution, dried (MgSO4), and evaporated to give a residue which was dissolved in methylene chloride (490 mL) and treated with diethylamine (51 mL, 5 eq.) and tetrakis triphenylphosphinepalladium (115 mg, 0.001 eq). After stirring for 2 h at room temperature, the volatiles were removed under reduced pressure and the residue was purified by chromatography on silica gel eluting with 10-20% methanol in ethyl acetate to give 4-acetyl-2,3,4,5-tetrahydro-1H-1,4-benzodiazepin-1-ylamine (13.5 g, 44%) as a white solid.

Provenance & Evidence