反应详情

4-Bromopyridine hydrochloride (4×2g) was added during one hour to a mixture of 1-[2-[4-[5-(2-methyltetrazol-5-yl)-1H-indol-3-yl]-1,2,3,6-tetrahydro-1-pyridinyl]ethyl]-2-imidazolidinone (4a) (5 g), potassium carbonate (9 g), copper powder (1 g), copper iodide (0.3 g), zinc oxide (0.3 g) and N-methyl-2-pyrrolidinone (NMP) (75 mL) at 140-150° C. Heating was continued for additional 4 hours. After cooling, ethyl acetate (500 mL) was added. Inorganic salts were filtered off. Water was added and the organic phase was worked up according to the standard procedure above. The remaining crude product was purified by column chromatography on silica gel, eluted with a 50:50:4 mixture of ethyl acetate, ethanol, and triethylamine. Yield 0.7 g of the title compound 5a. mp 177-178° C. 1H NMR (DMSO-d6) δ 2.55-2.65 (m, 4H), 2.75 (t, 2H), 3.20-3.30 (m, 6H) 3.40 (t, 2H), 4.45 (s. 3H), 6.25 (s, 1H), 6.30 (broad t, 1H), 7.75 (dd, 2H, 7.90-8.00 (m, 3H), 8.60 (s, 1H), 8.75 (d, 2H), MS m/z (%): 236 (MH2++), 272 (9%), 245 (17%), 142 (65%), 113 (100%).

1. temperatureHeating
2. temperatureAfter cooling
3. filtrationInorganic salts were filtered off
4. additionWater was added
5. customThe remaining crude product was purified by column chromatography on silica gel
6. washeluted with a 50:50:4 mixture of ethyl acetate, ethanol, and triethylamine