反应详情

温度

25 °C

Subsequently, 4-methyl-5-(2-nitrooxy-ethyl)-thiazole-2-ylamine was prepared by drop-wise addition of 1.59 grams of nitric acid (70%) to 2.48 grams of cooled sulfuric acid (95-98%) at 0-5° C. over a time period of 20 minutes. Following, 4 grams (0.025 moles) of 2-(2-Amino-4-methyl-thiazol-5-yl)-ethanol were added over a time period of 45 minutes at 0-5° C. After the addition was completed, the reaction mixture was stirred for 3 hours at 25° C., and was then added carefully to 50 ml of cold water. The water solution was turned basic with an aqueous solution of 20% sodium hydroxide and the aqueous phase was extracted with three portions of 75 grams of ethyl acetate. The organic extracts were combined, dried over sodium sulfate, filtered and evaporated to dryness under vacuum. Chromatography of the crude product on silica gel (using a mixture of 8:2 ethyl acetate:hexane as eluent) gave 1.8 grams (35% yield) of the product as orange oil having a purity of 98.5% as determined by gas chromatography.

1. additionAfter the addition
2. extractionthe aqueous phase was extracted with three portions of 75 grams of ethyl acetate
3. dry with materialdried over sodium sulfate
4. filtrationfiltered
5. customevaporated to dryness under vacuum
6. additiona mixture of 8:2 ethyl acetate