反应详情

A stirred solution of 133 (0.78 g, 3.8 mmol), PPh3 (1.1 g, 4.3 mmol), imidazole (0.40 g, 5.8 mmol), and CH3CN (20 mL) at 0° C. was treated with iodine (1.0 g, 4.3 mmol). After 15 min the cooling bath was removed and stirring continued for 5 h. The reaction mixture was then diluted with H2O and extracted with hexanes (5×25 mL then 4×50 mL). The combined extracts were dried (MgSO4) and concentrated. Flash chromatography (silica, 20% EtOAc/hexanes) gave 134 (0.99 g) as a colorless oil. Rf 0.44 (silica, 20% EtOAc/hexanes). 1H NMR (400 MHz, CDCl3) δ 4.04 (t, J=7 Hz, 2H), 3.57 (dd, 2H), 3.10 (t, 2H), 2.64 (m, 1H), 2.16 (q, 2H), 1.43 (s, 9H). ##STR59##

1. customAfter 15 min the cooling bath was removed
2. additionThe reaction mixture was then diluted with H2O
3. extractionextracted with hexanes (5×25 mL
4. dry with materialThe combined extracts were dried (MgSO4)
5. concentrationconcentrated