反应详情

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).

1. customThe mixture was partitioned between ethyl ether (100 mL) and water
2. customthe organic layer was separated
3. washwashed with additional water (3×) and saturated aqueous sodium chloride
4. dry with materialdried over anhydrous magnesium sulfate
5. filtrationfiltered
6. concentrationconcentrated in vacuo
7. customto afford a colorless oil
8. customThe residue was purified by silica gel flash chromatography