反应详情

1 N NaOH (75 mL) was added to a stirred suspension of (R)-N5 -(Cbz)-ornithine hydrochloride (7.5 g; 25 mmol) in THF (114 mL). Once the starting material had dissolved, diphenylacetyl chloride (6.7 g; 26.3 mmol) was added. The reaction was stirred for 3 h at room temperature, then made acidic with cold 1 N HCl and extracted with EtOAc (3×75 mL). The EtOAc extract was washed with brine, dried with Na2SO4, and concentrated to afford the crude product. Purification by flash chromatography on silica eluting with EtOAc:hexanes (1:1) afforded the sub-title compound (10.5 g; 91%).

1. dissolutionOnce the starting material had dissolved
2. extractionextracted with EtOAc (3×75 mL)
3. extractionThe EtOAc extract
4. washwas washed with brine
5. dry with materialdried with Na2SO4
6. concentrationconcentrated
7. customto afford the crude product
8. customPurification by flash chromatography on silica eluting with EtOAc:hexanes (1:1)