Nitric Acid → 1-Methyl-4-nitro-1H-imidazole-2-carbaldehyde

Fuming nitric acid (3 ml) was cooled to -10° C., to which 3 ml of concentrated sulfuric acid were added dropwise. The resulting mixture was added dropwise at an internal temperature of -10° C. or lower to 0.5 g (4.54 mmol) of 2-formyl-1-methylimidazole. The temperature of the thus-obtained was naturally allowed to rise to room temperature, at which the mixture was allowed to stand overnight. The reaction mixture was poured into ice, followed by neutralization with sodium carbonate. The resultant mixture was extracted twice with methylene chloride. The organic layers were washed with a saturated aqueous solution of sodium hydrogencarbonate, dried over sodium sulfate and then concentrated. The residue was crystallized from ethyl ether/ethanol, whereby 0.21 g (1.35 mmol) of the title compound was obtained as cream-colored crystals (yield: 29.8%).

1. additionwere added dropwise
2. customto rise to room temperature, at which
3. additionThe reaction mixture was poured into ice
4. extractionThe resultant mixture was extracted twice with methylene chloride
5. washThe organic layers were washed with a saturated aqueous solution of sodium hydrogencarbonate
6. dry with materialdried over sodium sulfate
7. concentrationconcentrated
8. customThe residue was crystallized from ethyl ether/ethanol

ORD record

ord-9ba558ce16094593b1ed6603cc94ffef

Source dataset

uspto-grants-1998_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05852011