反应详情

A suspension of 32 g of the crude resultant compound of Example 1 E and 55.5 g (176 mmol) of barium hydroxide octahydrate in 400 ml of 1,4-dioxane and 400 ml of water was heated at reflux for 4 h. The resulting mixture was filtered, and the residue was rinsed with dioxane. The combined filtrates were concentrated to a volume of approximately 200 ml and extracted with four 400 ml portions of chloroform. The combined organic layers were dried over Na2SO4, filtered, and concentrated in vacuo. The residue was purified by silica gel chromatography using first 2% isopropylamine in chloroform and then 2% isopropylamine/2% methanol in chloroform to provide 10.1 g (81%) of the pure desired compound as a white solid. 1H NMR (CDCl3) δ 1.54 (dt, J=14, 10 Hz, 1H), 1.67 (dt, J=14, 3 Hz, 1H), 2.50 (dd, J=13, 8 Hz, 1H), 2.58 (dd, J=13,8Hz, 1H), 2.8 (m, 2H), 2.91 (dd, J=13,5 Hz, 1H), 3.10 (m, 1H), 3.72 (ddd, J=11,3,2 Hz, 1H), 7.1-7.4 (m, 10H). Mass spectrum: (M+H)+ =285.

1. temperaturewas heated
2. temperatureat reflux for 4 h
3. filtrationThe resulting mixture was filtered
4. washthe residue was rinsed with dioxane
5. concentrationThe combined filtrates were concentrated to a volume of approximately 200 ml
6. extractionextracted with four 400 ml portions of chloroform
7. dry with materialThe combined organic layers were dried over Na2SO4
8. filtrationfiltered
9. concentrationconcentrated in vacuo
10. customThe residue was purified by silica gel chromatography