反应详情

To a flask containing compound 4b (30 mg, 0.0358 mmol) at 0-5° C. was added dropwise 4M HCl (g) in 1,4-dioxane (2 mL) over 10 min. The resulting mixture was gradually warmed to room temperature and continuously stirred for 40 h. Ether (20 mL) was added to the reaction mixture which was then stirred for 10 min. The resulting precipitate was filtered and washed with ether. The solid product was quickly dissolved deionized water. The aqueous solution was concentrated in vacuo to provide 5b (24 mg, 100%) as an off-white solid. 1H NMR (D2O, 300 MHz) δ1.03-1.89 (m, 4H), 2.21-4.32 (m, 20H), 7.27 (s, 2H), 7.97 (s, 2H); 13C NMR (D2O, 300 MHz) δ25.0 (t), 26.3 (t), 34.6 (t), 46.9 (t), 48.7 (t), 52.3 (t), 52.7 (t), 53.6 (t), 54.6 (t), 55.3 (t), 62.4 (d), 123.7 (d), 129.4 (d), 145.9 (s), 150.0 (s), 168.5 (s), 170.5 (s), 172.7 (s).

1. stirringwas then stirred for 10 min
2. filtrationThe resulting precipitate was filtered
3. washwashed with ether
4. dissolutionThe solid product was quickly dissolved
5. concentrationThe aqueous solution was concentrated in vacuo