Imidazole → 4-(1H-imidazol-1-yl)benzaldehyde

To a suspension of sodium hydride (60% in oil: 0.82 g, 20.5 mmol) in dry DMF (4.5 ml) under nitrogen atmosphere is added imidazole (1.37 g, 20.1 mmol) with stirring at room temperature. After being stirred for 20 min. 4-bromobenzaldehyde dimethyl acetal (4.63 g, 20 mmol) and copper powder (0.13 g, 2.0 mmol) are added and the reaction mixture is stirred at 130° C. for 2 h, then at 150° C. for 2.5 h. The mixture is cooled to room temperature, diluted with chloroform and water. The solution is stirred for 1 h and filtered on Celite. The organic layer is separated, washed wit water, dried over sodium sulfate, and concentrated in vacuo. The residue is dissolved in 1N hydrochloric acid (20 ml) and stirred at room temperature for 4 h. The reaction mixture is diluted with 5N NaOH (4 ml), and extracted with ethyl acetate. The organic layer is washed with brine, dried over sodium sulfate, and concentrated in vacuo. The solid obtained is washed with hexane and dried in vacuo to give 4-(1-imidazolyl)benzaldehyde.

1. stirringAfter being stirred for 20 min
2. stirringthe reaction mixture is stirred at 130° C. for 2 h
3. temperatureThe mixture is cooled to room temperature
4. stirringThe solution is stirred for 1 h
5. filtrationfiltered on Celite
6. customThe organic layer is separated
7. washwashed wit water
8. dry with materialdried over sodium sulfate
9. concentrationconcentrated in vacuo
10. dissolutionThe residue is dissolved in 1N hydrochloric acid (20 ml)
11. stirringstirred at room temperature for 4 h
12. additionThe reaction mixture is diluted with 5N NaOH (4 ml)
13. extractionextracted with ethyl acetate
14. washThe organic layer is washed with brine
15. dry with materialdried over sodium sulfate
16. concentrationconcentrated in vacuo
17. customThe solid obtained
18. washis washed with hexane
19. customdried in vacuo

ORD record

ord-4fb1334d5f4d4eaea3bfa7772dd57e9c

Source dataset

uspto-grants-1998_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05780498