反应详情

A solution of methyl-2-(4-isopropylanilino)acetate (1.10 g, 5.31 mmol) in toluene (30 mL) was treated with methyl 3-isocyanatobenzoate (1.03 g), and the resulting solution was stirred at ambient temperature for 20 h. The reaction mixture was evaporated, and a portion (0.6 g) of the resulting solid material used directly in the next step. The compound was dissolved in methanol, and treated with sodium methoxide (0.84 mL of 0.5 M in methanol). The resulting solution was stirred for 1 h, then evaporated and partitioned between water and ethyl acetate (50 mL each). The organic extract was washed with brine, dried over magnesium sulfate, filtered and evaporated. The residual material was separated by preparative thin-layer chromatography (silica gel, 30:70 ethyl acetate-hexane) to afford pure product, methyl-3-[3-(4-isopropylphenyl)-2,5-DIOXO-imidazolidin-1-yl]-benzoate, as a waxy solid. 1H NMR (CDCl3, 300 MHz): δ 8.16 (1H, t, J=1.8 Hz), 8.07 (1H, dt, J=7.6, 1.5 Hz), 7.67 (1H, ddd, J=8.0, 2.0, 1.1 Hz), 7.56 (1H, t, J=7.9 Hz), 7.51 (2H, d, J=8.8 Hz), 7.27 (2H, d, J=8.8 Hz), 4.47 (2H, s), 3.92 (3H, s), 2.91 (1H, m, J=7.0 Hz), 1.25 (6H, d, J=7.0 Hz). Mass spectrum (ES+): m/z 353 (36), 321 (100).

1. customThe reaction mixture was evaporated
2. dissolutionThe compound was dissolved in methanol
3. additiontreated with sodium methoxide (0.84 mL of 0.5 M in methanol)
4. stirringThe resulting solution was stirred for 1 h
5. customevaporated
6. custompartitioned between water and ethyl acetate (50 mL each)
7. extractionThe organic extract
8. washwas washed with brine
9. dry with materialdried over magnesium sulfate
10. filtrationfiltered
11. customevaporated
12. customThe residual material was separated by preparative thin-layer chromatography (silica gel, 30:70 ethyl acetate-hexane)