反应详情

温度

0 °C

8 g of the product obtained in Stage B is dissolved at 40° C. in 60 ml of glacial acetic acid. Then a solution of 5 ml of concentrated sulphuric acid in 80 ml of water is added. The reaction medium is cooled down to 0° C. Then a solution of 2.77 g of sodium nitrite in 35 ml of water is added dropwise over one hour. Agitation is carried out for one hour at 0° C., and a solution of 13.33 g of potassium iodide, in 25 ml of water is added dropwise. The suspension obtained is maintained at 0° C. for one hour, brought to 10° C. over 40 minutes, maintained at 10° C. for one hour, and brought to 20° C. over 30 minutes. It is poured into water, and extraction is carried out with ethyl acetate. The organic phases are collected and washed (aqueous solution of NaHSO3 then NaHCO3). They are dried and evaporated under reduced pressure. The product obtained is chromatographed, eluting with a heptane-methylene chloride mixture (9-1) and 9.6 g of sought product is obtained, melting at 57° C.

1. customThe suspension obtained
2. temperatureis maintained at 0° C. for one hour
3. waitbrought to 10° C. over 40 minutes
4. temperaturemaintained at 10° C. for one hour
5. waitbrought to 20° C. over 30 minutes
6. customThe organic phases are collected
7. washwashed (aqueous solution of NaHSO3
8. customThey are dried
9. customevaporated under reduced pressure
10. customThe product obtained
11. customis chromatographed
12. washeluting with a heptane-methylene chloride mixture (9-1)