Formaldehyde → HCID 22065971, compound

Participants

Reaction Steps

1-Phenylpiperazine (1.63 g, 10.0 mmol), and sodium acetate trihydrate (1.36 g, 10 mmol) were dissolved in acetic acid (4 ml) and water (2 ml). 37% Aqueous formaldehyde (0.9 ml, 12 mmol) was added and the reaction mixture stirred for five minutes. 1H-Pyrrolo[2,3-b]pyridine (1.18 g, 10 mmol) was added, and the resulting solution stirred at room temperature overnight. The reaction mixture was poured into 2M sodium hydroxide solution (50 ml) and extracted with ethyl acetate (2×50 ml). The extracts were washed with brine (50 ml), combined and dried (MgSO4). The ethyl acetate solution was concentrated in vacuo to about one quarter of the original volume and the precipitated yellow solid was collected by filtration and recrystallised from toluene to yield the title compound (1.20 g), as pale lemon crystals. This material was further recrystallised from methanol to give pale lemon needles, m.p. 207°-209° C; (Found: C, 73.91; H, 7.09; N, 19.31. C18H20N4 requires C, 73.94; H, 6.90; N, 19.16%); δH (DMSO-d6) 2.53 (4H, t, J 5Hz, 2×CH2N), 3.10 (4H, t, J 5Hz, 2×CH2N), 3.68 (2H, s, indole-CH2N), 6.75 (1H, t, J 7Hz, 4'-H), 6.89 (2H, d, J 8 Hz, 2'-H, 6'-H), 7.04 (1H, dd, J 8, 4.5 Hz, 5-H), 7.18 (2H, t, J 8Hz, 3'-H, 5'-H), 8.05 (1H, dd, J 8, 1.5 Hz, 4-H), 8.19 (1H, dd, J 4.5, 1.5 Hz, 6-H), and 11.45 (1H, br s, NH); m/z (CI+, NH3) 293 (M+ 1)+.

Provenance & Evidence