反応 #577219

反応方程式

3-Bromo-1-propene

7-hydroxy-4-methylcoumarin

potassium carbonate

→

2

収率 96.2%

7-Allyloxy-4-methylcoumarin

収率 96.2%

溶媒

acetone

反応条件

後処理

1. 1
   温度The resulting mixture was then refluxed for 4 h
2. 2
   温度to cool
3. 3
   ろ過the K2CO3 filtered off
4. 4
   洗浄washed with fresh acetone
5. 5
   その他The solvent was removed in vacuo
6. 6
   その他the residue was crystallized from methanol

実験手順

3-Bromo-1-propene (2.95 mL, 34.06 mmol) was added dropwise under argon to a stirred mixture of 7-hydroxy-4-methylcoumarin 1 (2.0 g, 11.35 mmol) and anhydrous potassium carbonate (K2CO3) (2.35 g, 17.03 mmol) in acetone (50 mL). The resulting mixture was then refluxed for 4 h, after which it was allowed to cool, and the K2CO3 filtered off and washed with fresh acetone. The solvent was removed in vacuo and the residue was crystallized from methanol to afford 2 as white-cream crystals (2.36 g, 96%). TLC (hexane/ethyl acetate, 1:3): Rf=0.63. mp 110° C. 1H NMR (CDCl3, 500 MHz) δ 2.39 (s, 3H, CH3), 4.60 (d, J=5.0 Hz, 2H, CH2), 5.33 (d, J=10.5 Hz, 1H), 5.44 (d, J=17.5 Hz, 1H), 6.05 (m, 1H), 6.12 (s, 1H), 6.80 (s, 1H), 6.87 (dd, J=1.5, 9.0 Hz, 1H), 7.49 (d, J=9.0 Hz, 1H). 13C NMR (CDCl3, 125 MHz) δ 18.70, 69.29, 101.84, 112.05, 112.79, 113.75, 118.51, 125.64, 132.31, 152.61, 152.26, 161.26, 161.65. ESIMS calcd for C13H13O3 [M+H]+ 217.1, found 217.1.

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