反应详情

Suspend 300 mg. of the cyano compound of Step 1 in 8 ml. of 20% aqueous sodium hydroxide and 8 ml. of absolute ethanol. Reflux under nitrogen for 2 hours. Evaporate the ethanol. Acidify the suspension with 20% hydrochloric acid and separate the solids by filtration. Dissolve the residue in 20 ml. of hot methanol and add a few drops of concentrated hydrochloric acid. Evaporate the methanol, dilute with ether and evaporate again. Dilute with water, stir for 30 minutes, and filter. Wash the solids with water and dry in vacuo at 100° C. to obtain the title product (m.p., 270°-272° C.).

1. temperatureReflux under nitrogen for 2 hours
2. customEvaporate the ethanol
3. customseparate the solids
4. filtrationby filtration
5. dissolutionDissolve the residue in 20 ml
6. additionof hot methanol and add a few drops of concentrated hydrochloric acid
7. customEvaporate the methanol
8. additiondilute with ether
9. customevaporate again
10. additionDilute with water
11. filtrationfilter
12. washWash the solids with water
13. customdry in vacuo at 100° C.