反応 #47110

反応方程式

4-chromanol

dichloromethane

ethyl diazoacetate

→

product 475

[(1-Benzopyran-4-yloxy)methyl]acetic acid ethyl ester

溶媒

heptane

反応条件

後処理

1. 1
   ろ過filtered through Celite
2. 2
   その他the filtrate is evaporated
3. 3
   その他the residue purified by chromatography on silica gel
4. 4
   洗浄elution with EtOAc:dichloromethane:hexane (10:20:70)

実験手順

To a solution of 4-chromanol (1.5 g, 10.0 mmol) in dichloromethane (20 mL) is added rhodium (II) acetate dimer (10 mg) followed by ethyl diazoacetate (0.95 mL, 9.0 mmol). The reaction mixture is stirred at rt for 30 min. The reaction mixture is diluted with heptane, filtered through Celite, and the filtrate is evaporated and the residue purified by chromatography on silica gel; elution with EtOAc:dichloromethane:hexane (10:20:70) gives 1.81 g of the product 475. 1H NMR (CDCl3) δ 7.35 (dd, 1H), 7.22 (dt, 1H), 6.90 (t, 1H), 6.84 (d, 1H), 4.56 (m, 1H), 4.36 (dd, 1H), 4.29 (dd, 1H), 4.23 (q, 2H), 4.19 (s, 2H), 2.18 (m, 1H), 2.05 (m, 1H), 1.30 (t, 3H); MS: m/z 236 (M++1).

出典