反应详情

5.0 g of ethyl 2-(2-amino-4-thiazolyl)-2-[(Z)-(cyanomethoxy)imino]-acetate are heated to 60° C. for 48 hours while stirring together with 1.95 g of sodium azide and 1.6 g of ammonium chloride in 50 ml of dimethylformamide. The mixture is taken up in water/ethyl acetate. The ethyl acetate phase is washed twice with a small amount of water. The combined aqueous phases are concentrated to dryness, the residue is dissolved in 50 ml of 1N aqueous sodium hydroxide solution and stored at room temperature for 1 hour. The mixture is subsequently diluted with 50 ml of water and the solution is concentrated to 50 ml. The product crystallizes after the addition of 50 ml of aqueous 1N hydrochloric acid. There are obtained 3.9 g of 2-(2-amino-4-thiazolyl)-2-[(Z)-(1H-tetrazol-5-yl-methoxy)imino]-acetic acid of melting point 151°-152° C. The water content is 6.96%.

1. washThe ethyl acetate phase is washed twice with a small amount of water
2. concentrationThe combined aqueous phases are concentrated to dryness
3. dissolutionthe residue is dissolved in 50 ml of 1N aqueous sodium hydroxide solution
4. additionThe mixture is subsequently diluted with 50 ml of water
5. concentrationthe solution is concentrated to 50 ml
6. customThe product crystallizes
7. additionafter the addition of 50 ml of aqueous 1N hydrochloric acid