反应详情

A mixture of 2-chloro-6-(1-methoxycarbonyl-2-oxo-propyl)-benzoic acid (4 g, 15 mmol), aniline (1.369 ml, 15 mmol) and tetraethoxysilane (6.65 ml, 30 mmol) in methanol (20 ml) was sealed and heated under microwave irradiation at +150° C. for 20 min. The obtained solution was diluted with water (150 ml) and extracted with ethyl acetate (2×300 ml). The combined organic solution was dried (MgSO4) and evaporated. The obtained crude enamine (2-chloro-6-(1-methoxycarbonyl-2-phenylamino-propenyl)-benzoic acid) was dissolved in dimethylformamide (80 ml) followed by addition of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC, 4.3 g, 22.5 mmol) and 1-hydroxybenzotriazole (HOBT, 3.04 g, 22.5 mmol). It was stirred for 16 hours and partitioned between water (250 ml), diethyl ether (250 ml) and ethyl acetate (150 ml). The organic phase was washed with 0.5 M NaOH (2×100 ml), brine (2×200 ml), dried (MgSO4) and evaporated to give 4.25 g of brown oil, which was used in the next step without further purification. Yield 87%. LC-MS (m/z) 328.0 (MH+); tR=1.36. 1H NMR (500 MHz, CDCl3): 2.02 (s, 3H), 3.98 (s, 3H), 7.23 (d, 2H), 7.44-7.55 (m, 6H).

1. customwas sealed
2. temperatureheated under microwave irradiation at +150° C. for 20 min
3. extractionextracted with ethyl acetate (2×300 ml)
4. dry with materialThe combined organic solution was dried (MgSO4)
5. customevaporated
6. customThe obtained crude enamine (2-chloro-6-(1-methoxycarbonyl-2-phenylamino-propenyl)-benzoic acid)
7. custompartitioned between water (250 ml), diethyl ether (250 ml) and ethyl acetate (150 ml)
8. washThe organic phase was washed with 0.5 M NaOH (2×100 ml), brine (2×200 ml)
9. dry with materialdried (MgSO4)
10. customevaporated