Ammonia → HCID 67923525, compound

Participants

Reaction Steps

A suspension of 1H-indole-5-carboxamide (0.4 g) in galcial acetic acid (20 ml) was heated to 80°under nitrogen, and the resulting solution was treated with aqueous phosphoric acid (2N; 7 ml). Freshly distilled 1-benzyl-4-piperidone (1.4 g) in glacial acetic acid (5 ml) was added and the reaction mixture was stirred at 70° for 18 h, cooled, and poured into a mixture of ice and 0.88 ammonia solution (50 ml) with ice bath cooling. Ethyl acetate (50 ml) was added and the layers were separated. The aqueous layer was extracted with ethyl acetate (4×60 ml), and the combined organic extracts were dried (MgSO4) and evaporated to dryness. The resulting oil was chromatographed on Merck Kieselgel 60 (100 g) eluting with 10% methanol in ethyl acetate. Evaporation of the solvent gave a foam which was treated with maleic acid in methanol/ether to give the title compound as microcrystals (0.19 g), m.p. 164°-166°.

Provenance & Evidence