反应详情

A solution of ethyl 4-amino-1H-imidazol-2-carboxylate (2.0 g, 12.9 mmol) (E. Gomez, C. Avendano and A. McKillop, Tetrahedron 1986, 42, 2635) in ethanol (50 ml) and 1M aqueous sodium hydroxide (14 ml) was refluxed for 20 minutes. The reaction mixture was concentrated to 20 ml and the pH of the solution adjusted to 5 with concentrated hydrogen chloride. The solid which precipitated, collected by filtration and washed with ethanol and ether to give the title compound (1.5 g, 32%). NMR: δ 7.07 (s, 1H).

1. concentrationThe reaction mixture was concentrated to 20 ml
2. customThe solid which precipitated
3. filtrationcollected by filtration
4. washwashed with ethanol and ether