2-[(Dimethylamino)methylidene]cyclohexane-1,3-dione → HCID 59490507, compound

Participants

Reaction Steps

To anhydrous ethanol (15 mL) was added sodium metal (0.45 g, 19.5 mmol). After complete dissolution of sodium metal in ethanol, 2-((dimethylamino)methylene)cyclohexane-1,3-dione (1 g, 5.5 mmol) and N-methylguanidine hydrochloride (1 g, 9.0 mmol) were added and the reaction was refluxed for 4 hours. The reaction mixture was cooled to room temperature and concentrated under reduced pressure. Ice-cooled water (50 mL) was then added to the residue and the aqueous solution extracted with EtOAc (3×40 mL). The combined organic extract was dried using sodium sulfate and concentrated under reduced pressure to give the desired product (0.6 g, 57%) as a solid. The crude product was used in the next step without further purification. 1H NMR (CDCl3, 400 MHz): δ 8.90 and 8.80 (2s, 1H), 5.98 and 5.82 (2s, 1H), 3.11 and 3.09 (2s, 3H), 2.96-2.88 (m, 2H), 2.58 (t, J=6.0 Hz, 2H), 2.10 (quintet, J=6.0 Hz, 2H). LCMS [M+H]: 178.

Provenance & Evidence