Formaldehyde → HCID 86631765, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of ethanol (40 mL), methylammonium methanesulfonate (MAMS) (16.5 g, 130 mmol), 2-acetylthiophene (11.0 g, 87.2 mmol) and paraformaldehyde (2.6 g, 86.6 mmol) in an autoclave is heated to 120° C. at a total pressure of 4.5 bar. After 3 h at that temperature, the autoclave is cooled to 25° C. The reaction mixture is concentrated to dryness and a mixture of ethanol (20 mL) and ethyl acetate (400 mL) is added to the residue, then the resulting suspension is stirred for 30 minutes at 25° C. Afterwards, the precipitate is filtrated, washed with ethyl acetate (40 mL) and unloaded from the filter. The crude material is then suspended in a mixture of ethyl acetate (200 mL) and ethanol (50 mL), heated to reflux and cooled to 0° C. Once cold, the suspension is stirred for 1 h at that temperature. The precipitate is then filtrated, washed with ethyl acetate (40 mL) and dried at 40° C. under vacuum (20 mbar) for 15 h affording a white-beige solid (19.4 g, 50%, 3-methylamino-1-thiophen-2-yl-propan-1-one mesylate according to 1H-NMR); 1H-NMR (DMSO-d6, 400 MHz): 8.5 (2H, s, broad), 8.1 (1H, dm), 8.0 (1H, dm), 7.30 (1H, dd), 3.42 (2H, t), 3.3 (2H, s, broad), 2.6 (3H, s, broad), 2.38 (3H, s); 13C-NMR (DMSO-d6, 100 MHz): 189.9, 142.6, 135.4, 133.9, 128.0, 43.2, 39.6, 34.5, 32.7.

Provenance & Evidence