反应详情

温度

60 °C

A suspension of (S)-2-amino-4-methyl-hexanoic acid ethyl ester hydrochloride salt (1.05 g, 5.01 mmol) in acetonitrile (6 mL) was treated with N,N-diisopropylethylamine (1.0 mL) and stirred at 60° C. for 15 min. To this mixture was added N,N-diisopropylethylamine (1.2 mL) and a solution of (E)-4-bromo-3-(2-chloro-phenoxy)-but-2-enoic acid ethyl ester (prepared in Example 61, 1.6 g, 5.0 mmol) in acetonitrile (4 mL) via a dropping funnel and the resulting mixture refluxed for 20 h. The resulting mixture was concentrated in vacuo and the residue was partitioned between ethyl acetate and water. The layers were separated and the organic layer was dried over sodium sulfate. The mixture was filtered and concentrated in vacuo and the residue dissolved in tetrahydrofuran (8 mL). The resulting solution was transferred to an Emrys Optimizer microwave tube and microwaved at 160° C. for 4 h. The mixture was concentrated in vacuo and the residue purified by ISCO flash chromatography (RediSep silica column 80 g, 20% to 80% ethyl acetate/hexanes) which afforded (S)-2-[4-(2-chloro-phenoxy)-2-oxo-2,5-dihydro-pyrrol-1-yl]-4-methyl-hexanoic acid ethyl ester (950 mg, 52%).

1. concentrationThe resulting mixture was concentrated in vacuo
2. customthe residue was partitioned between ethyl acetate and water
3. customThe layers were separated
4. dry with materialthe organic layer was dried over sodium sulfate
5. filtrationThe mixture was filtered
6. concentrationconcentrated in vacuo
7. dissolutionthe residue dissolved in tetrahydrofuran (8 mL)
8. custommicrowaved at 160° C. for 4 h
9. concentrationThe mixture was concentrated in vacuo
10. customthe residue purified by ISCO flash chromatography (RediSep silica column 80 g, 20% to 80% ethyl acetate/hexanes) which