triethylorthoformate Acetic anhydride → 6-Bromo-4-chloro-3-methyl-imidazo[4,5-c]pyridine
Reaktionsgleichung
[Br:1][C:2]1[N:7]=[C:6]([Cl:8])[C:5]([NH:9][CH3:10])=[C:4]([NH2:11])[CH:3]=1.[CH2:12](OC(OCC)OCC)C.C(OC(=O)C)(=O)C>>[Br:1][C:2]1[N:7]=[C:6]([Cl:8])[C:5]2[N:9]([CH3:12])[CH:10]=[N:11][C:4]=2[CH:3]=1Komponenten
3
Reaktionsbedingungen
- Temperatur
- 155 °C
Versuchsvorschrift
The above crude diamine 2.59-A was dissolved in a mixture of triethylorthoformate:Acetic anhydride (1:1, 9 mL). The reaction mixture was heated to 155° C. for 1 h, cooled to rt and then evaporated. The residue was dissolved in 2.5M NaOH (20 mL) and heated at 50° C. 45 min. The resulting solution was cooled to rt, neutralized with AcOH, and cooled to 0° C. The precipitate was filtered to give 6-bromo-4-chloro-3-methyl-3H-imidazo[4,5-c]pyridine 2.60.