反应详情

Ethyl (2-methylthio-imidazol-1-yl)-acetate (14.5 g.) in 4 N sulphuric acid (30 cc.) is heated under reflux for 1 hour. The sulphate ions are then removed by adding an aqueous solution of barium hydroxide and filtering off the precipitated barium sulphate. The filtrate is treated with decolorising charcoal and is then concentrated to dryness under reduced pressure (20 mm.Hg). The residue is taken up in benzene (80 cc.) and the mixture is again concentrated to dryness under reduced pressure (20 mm.Hg); this step is then repeated. Purification of the product by recrystallisation from dimethylformamide (30 cc.) yields (2-methylthio-imidazol-1-yl)-acetic acid (7.5 g.), m.p. 176° C.

1. temperatureunder reflux for 1 hour
2. customThe sulphate ions are then removed
3. additionby adding an aqueous solution of barium hydroxide
4. filtrationfiltering off the precipitated barium sulphate
5. additionThe filtrate is treated with decolorising charcoal
6. concentrationis then concentrated to dryness under reduced pressure (20 mm.Hg)
7. concentrationthe mixture is again concentrated to dryness under reduced pressure (20 mm.Hg)
8. customPurification of the product
9. customby recrystallisation from dimethylformamide (30 cc.)