反応 #499888

反応方程式

ethyl salicylate

cesium carbonate

dimethylformamide

tert-butyl 4-chlorobutyrate

→

ethyl 2-(3-tert-butoxycarbonylpropoxy)benzoate

収率 62.0%

溶媒

ethyl acetate

反応条件

後処理

1. 1
   その他The mixture was partitioned between ethyl ether (100 mL) and water
2. 2
   その他the organic layer was separated
3. 3
   洗浄washed with additional water (3×) and saturated aqueous sodium chloride
4. 4
   乾燥dried over anhydrous magnesium sulfate
5. 5
   ろ過filtered
6. 6
   濃縮concentrated in vacuo
7. 7
   その他to afford a colorless oil
8. 8
   その他The residue was purified by silica gel flash chromatography

実験手順

A mixture comprising ethyl salicylate (3.14 g, 18.9 mmol) and cesium carbonate (6.2 g, 18.9 mmol), dimethylformamide (25 mL) and tert-butyl 4-chlorobutyrate (4.08 g, 22.8 mmol) was heated at 70° C. and stirred for 12 hours. The mixture was partitioned between ethyl ether (100 mL) and water and the organic layer was separated and washed with additional water (3×) and saturated aqueous sodium chloride, dried over anhydrous magnesium sulfate, filtered and concentrated in vacuo to afford a colorless oil. The residue was purified by silica gel flash chromatography using pure hexane to (10:1) hexane:ethyl acetate to provide ethyl 2-(3-tert-butoxycarbonylpropoxy)benzoate (3.6 g, 62% yield) as a colorless oil; 1H NMR (300 MHz, CDCl3): 7.80 (d, 1H), 7.49 (tr, 1H), 7.00 (m, 2H), 4.40 (q, 2H), 4.10 (tr, 2H), 2.50 (tr, 2H), 2.10 (m, 2H), 1.45 (s, 9H), 1.40 (tr, 3H).

出典