反应详情

Step AS (3). To a solution of 2-allyloxy-5-methoxybenzyl alcohol (5 g, 26 mmol) in 75 mL of anhydrous THF was added diphenylphosphoryl azide (6 mL, 28.5 mmol) and 1,8-diazabicyclo[5,4,0]undec-7-ene (DBU) (4.6 mL, 31 mmol) at 0° C. The mixture was refluxed for 1 h. The reaction was concentrated and the residue purified by silica gel chromatography eluting with 25% EtOAc in hexane to yield 2-allyloxy-5-methoxybenzyl azide as a colorless oil (4.9 g, 87%). (M−N3)+=177; 1H NMR (400 MHz, CDCl3) δ ppm 3.76 (s, 3H) 4.36 (s, 2H) 4.47-4.57 (m, 2H) 5.21-5.31 (m, 1H) 5.31-5.46 (m, 1H) 5.95-6.14 (m, 1H) 6.79-6.82 (m, 2H) 6.83-6.85 (m, 1H).

1. temperatureThe mixture was refluxed for 1 h
2. concentrationThe reaction was concentrated
3. customthe residue purified by silica gel chromatography
4. washeluting with 25% EtOAc in hexane