反应详情

Add to a solution of 4-benzyloxycarbonyl-1-allylpiperazin-2-one (1.1 g, 4.0 mmol) in dry THF (4 mL/mmol) at −78° C. under nitrogen lithium bis(trimethylsilyl)amide (1.OM solution in THF, 4.0 mL, 4.0 mmol) dropwise and stir 30 min. Add 2-(dibenzylamino)-3-phenylpropanal (732 mg, 2.2 mmol) in dry THF (2 mL/mmol) and stir at −78° C. for 45 min. Quench with saturated aqueous ammonium chloride solution. Separate organic layer and wash with water, saturated aqueous sodium chloride solution, dry (magnesium sulfate), concentrate and purify (silica gel chromatography, eluting with 100% hexanes to 1:1 hexanes:ethyl acetate) to give a mixture of four diastereoisomers (836 mg, 62%). Separate the isomers by normal phase HPLC (95:5 hexanes:isopropanol 95/5) to provide:

1. customQuench with saturated aqueous ammonium chloride solution
2. washSeparate organic layer and wash with water, saturated aqueous sodium chloride solution
3. dry with materialdry (magnesium sulfate)
4. concentrationconcentrate
5. custompurify
6. wash(silica gel chromatography, eluting with 100% hexanes to 1:1 hexanes:ethyl acetate)
7. customto give
8. additiona mixture of four diastereoisomers (836 mg, 62%)
9. customSeparate the isomers by normal phase HPLC (95:5 hexanes:isopropanol 95/5)
10. customto provide