Formaldehyde → HCID 22065971, compound

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)+.

1. stirringthe resulting solution stirred at room temperature overnight
2. extractionextracted with ethyl acetate (2×50 ml)
3. washThe extracts were washed with brine (50 ml)
4. dry with materialdried (MgSO4)
5. concentrationThe ethyl acetate solution was concentrated in vacuo to about one quarter of the original volume
6. filtrationthe precipitated yellow solid was collected by filtration
7. customrecrystallised from toluene

ORD record

ord-116f2acdb7ec433db666a629e3c48d7b

Source dataset

uspto-grants-1995_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05432177