反应详情

温度

80 °C

In a small pressure bottle was placed a mixture 2-amino-3-(cis-3-methyl-cyclobutyl)-propionic acid methyl ester (133 mg, 0.78 mmol), acetonitrile (10 mL) and N,N-diisopropylethylamine (200 μL, 0.94 mmol) and the resulting mixture heated to 80° C. To this mixture was added (E)-4-bromo-3-(2-chloro-phenoxy)-but-2-enoic acid ethyl ester (prepared as in Example 61, 250 mg, 0.78 mmol) in dichloromethane (5 mL) and the tube sealed and heated at 100° C. overnight. The mixture was then cooled and concentrated in vacuo with silica gel (2 g). Purification by Biotage flash chromatography (40S column, 20% ethyl acetate/hexanes to 40% ethyl acetate/hexanes) afforded 2-[4-(2-chloro-phenoxy)-2-oxo-2,5-dihydro-pyrrol-1-yl]-3-(cis-3-methyl-cyclobutyl)-propionic acid methyl ester (103 mg, 36%) as an amber gum: HR-ES-MS m/z calculated for C19H22NO4Cl [M+Na]+ 386.1129, observed 386.1130.

1. customthe tube sealed
2. temperatureheated at 100° C. overnight
3. temperatureThe mixture was then cooled
4. concentrationconcentrated in vacuo with silica gel (2 g)
5. customPurification by Biotage flash chromatography (40S column, 20% ethyl acetate/hexanes to 40% ethyl acetate/hexanes)