反应详情

A mixture of 7.50 g (38.2 mmol) of methyl 3-(4-fluorophenyl)-3-oxopropanoate and 11.5 g (76.5 mmol) of 2-methyl-5-oxopyrrolidin-1-aminium chloride in 50 ml of pyridine is stirred at room temperature for 72 h. The reaction mixture is concentrated under reduced pressure. Purification by column chromatography on silica gel (cyclohexane/ethyl acetate) gives 10.4 g (93%) of the desired product as a mixture of isomers; log P(HCOOH): 2.13 and 2.45; 1H-NMR (ppm): δ (DMSO-d6)=1.16-1.19 (m, 3H), 1.58-1.62 (m, 2H), 2.20-2.22 (m, 1H), 2.36-2.41 (m, 1H), 3.54 (s, 2.25H), 3.64 (s, 0.75H), 3.80 (d, 1H), 3.90 (d, 1H), 3.80 (q, 1H), 7.24 (t, 0.6H), 7.29 (t, 1.4H), 7.44-7.47 (m, 0.6H), 7.89-7.92 (m, 1.4H); LC-MS: m/z=293 [M+H]+.

1. concentrationThe reaction mixture is concentrated under reduced pressure
2. customPurification by column chromatography on silica gel (cyclohexane/ethyl acetate)