反应详情

4-[(tert.-butoxycarbonyl)amino]butanoic acid (5.20 g, 25.6 mmol, prepared in analogy to Houssin et al., (1988) Synthesis 3, 259-261) was dissolved in anhydrous tetrahydrofuran (20 mL), carbonyldimidazole (CDI) (4.56 g, 28.1 mmol) was added and the resulting clear solution was stirred at room temperature for 2 h. Then, the primary amine 11 (3.11 g 25.6 mmol) and trietylamine (7.10 mL, 50.9 mmol) were added and stirring was continued at room temperature for 2 h. The solvent was removed under reduced pressure and the crude product was purified by column chromatography (silica gel, 40 g, chloroform/ethylacetate 1:1) to give compound 12 (3.59 g, 52%) as a light yellow oil (Rf 0.3, chloroform/ethyl acetate 1:1).

1. stirringstirring
2. waitwas continued at room temperature for 2 h
3. customThe solvent was removed under reduced pressure
4. customthe crude product was purified by column chromatography (silica gel, 40 g, chloroform/ethylacetate 1:1)