Sodium Hydroxide → 1-Methyl-4-nitropyrrole-2-carboxylic acid

Participants

Reaction Steps

Methyl 1-methyl-4-nitro-1H-pyrrole-2-carboxylate (5.0 g, 27.17 mmol) in 120 ml of 1:1 THF/H2O was added 8 g of NaOH in 30 ml of water. The mixture was stirred overnight, concentrated, diluted with water, extracted with EtAc/Hexane (1:1). The aqueous solution was adjusted to pH 3˜4 with 20% H3PO4 and extracted with EtAc (4×60 ml). The organic solutions were combined, dried over MgSO4, filtered, evaporated and crystallized with ethanol/EtAc/Hexane to afford 4.06 g (88%) of the title product. 1H NMR (DMSO) 13.12 (s, 1H), 8.21 (s, 1H), 7.25 (s, 1H), 3.91 (s, 3H); 13C NMR 160.97, 134.01, 129.16, 123.81, 111.38, 37.47; MS m/z−169.1 (M−H).

Provenance & Evidence