反应详情

To a stirred solution of Intermediate 350A (2.1 g, 4.14 mmol) in 1,4-dioxane (10.0 mL) was added 4 M HCl in dioxane (10 mL, 41 mmol) and the resulting solution stirred at RT for 1 h. The reaction mixture was concentrated and diluted with EtOAc (50 mL) The organic layer was washed successively with water, a saturated aq. solution of NaHCO3, and brine, then dried over Na2SO4, filtered and the filtrate concentrated under reduced pressure. The residue obtained was heated in a ROTAVAPOR® at 60° C. for 5 h. The solid product was triturated with diethyl ether to afford Intermediate 350B as a pale yellow solid (1.1 g, 60%). MS(ES): m/z=362 [M+H]+; 1H NMR (400 MHz, chloroform-d) δ ppm 6.93 (s, 1H), 4.41 (q, J=7.0 Hz, 2H), 4.26 (s, 2H), 1.41 (t, J=7.0 Hz, 3H), 1.11-0.85 (m, 4H).

1. concentrationThe reaction mixture was concentrated
2. additiondiluted with EtOAc (50 mL) The organic layer
3. washwas washed successively with water
4. dry with materiala saturated aq. solution of NaHCO3, and brine, then dried over Na2SO4
5. filtrationfiltered
6. concentrationthe filtrate concentrated under reduced pressure
7. customThe residue obtained
8. temperaturewas heated in a ROTAVAPOR® at 60° C. for 5 h
9. customThe solid product was triturated with diethyl ether