反应详情

12.75 g (39.5 mmol) C1 were dissolved in a mixture of 173 ml glacial acid, 136 ml tetrahydrofurane and 17 ml water. After cooling to 5° C. a solution of 3.24 g (47.0 mmol) sodium nitrite in 25 ml water was added keeping the temperature between 5° C. and 10° C. The cooling was removed and the mixture stirred for 6 hours at room temperature. After removal of the solvent in vacuo 320 ml water and 320 ml ethyl acetate were added. The pH was adjusted to 8 with 3 N NaOH. The phases were separated and the aqueous layer was extracted with 50 ml ethyl acetate. The combined organic layers were dried over sodium sulphate and the solvent was removed in vacuo. The residue was treated with diethylether, filtered off and dried. Yield: 8.33 g (60%) D1, m.p. 156–158° C.

1. additionwas added
2. customthe temperature between 5° C. and 10° C
3. customThe cooling was removed
4. customAfter removal of the solvent in vacuo 320 ml water and 320 ml ethyl acetate
5. additionwere added
6. customThe phases were separated
7. extractionthe aqueous layer was extracted with 50 ml ethyl acetate
8. dry with materialThe combined organic layers were dried over sodium sulphate
9. customthe solvent was removed in vacuo
10. additionThe residue was treated with diethylether
11. filtrationfiltered off
12. customdried