反应详情

A 100 mL mini-block tube equipped with a magnetic stir bar was charged with 4.56 g (20.0 mmol) of 2-hydroxy-4-methoxybenzophenone, 2.70 mL (3.68 g, 18.9 mmol) of ethyl 4-bromobutyrate and 40 mL of dimethylformainide (DMF). Potassium carbonate (2.96 g, 21.4 mmol) was added to the clear solution. The reaction mixture was heated to 80 C. After stirring for 20 hr at 25 C, the clear reaction mixture was diluted with water. The resulting solid was isolated by filtration. This solid was taken up in 30 mL of tetrahydrofuran (THF) and treated with 3.10 g (24.0 mmol) of potassium trimethylsilanoate. The orange solution was stirred for 20 hr at 25 C, diluted with aqueous 4% hydrochloric acid to pH 7.5 and washed with MTBE. The organic phase was extracted with aqueous 3% sodium bicarbonate solution. The combined aqueous phases were acidified to pH 2 with aqueous 4% hydrochloric acid and extracted with 60 mL of MTBE. This organic phase was washed with brine (1×40 mL), dried over sodium sulfate and concentrated. The resulting solid was purified by trituration using MTBE/hexanes. More of the product was isolated from the mother liquor. LC-MS analysis: m+1 peak confirmed (315). 1H NMR Analysis: (d6-DMSO): δ 12.0, bs, 1H (COOH); δ 7.6, d, 2H, (phenyl H's, o to CO); δ 7.56, t, 1H (phenyl H, p to CO); δ 7.44, t, 2H (phenyl H's, m to CO); δ 7.35, d, 1H (aryl H, o to CO); δ 6.64, m, 2H (aryl H's, m to CO); δ 3.88, t, 2H, (CH2 α to O); δ 3.82, s, 3H, (CH3O); δ 1.84, t, 2H (CH2 α to COOH); δ1.53, p, 2H (middle CH2 in chain). 13C NMR (d6-DMSO): 195.08, 173.91, 163.17, 158.33, 138.84, 132.37, 131.37, 128.67, 128.24, 120.87, 105.87, 99.02, 66.89, 55.53, 29.45, 23.79.

1. customA 100 mL mini-block tube equipped with a magnetic stir bar
2. temperatureThe reaction mixture was heated to 80 C
3. customThe resulting solid was isolated by filtration
4. stirringThe orange solution was stirred for 20 hr at 25 C
5. washwashed with MTBE
6. extractionThe organic phase was extracted with aqueous 3% sodium bicarbonate solution
7. extractionextracted with 60 mL of MTBE
8. washThis organic phase was washed with brine (1×40 mL)
9. dry with materialdried over sodium sulfate
10. concentrationconcentrated
11. customThe resulting solid was purified by trituration
12. customMore of the product was isolated from the mother liquor