反应详情

A solution of N-benzylglycine (12.39 g, 75 mmol), dimethyl maleate (6.26 g, 50 mmol), paraformaldehyde (4.5 g, 150 mmol) and DIEA (8.7 mL, 50 mmol) in toluene (100 mL) was stirred at reflux for 2 hours and concentrated. The residue was taken up in EtOAc. The solution was washed with brine 3×, dried (MgSO4) and concentrated. Column chromatography eluting with 50% EtOAc/hexanes provided dimethyl cis-1-benzyl-3,4-pyrrolidinedicarboxylate (4.8 g, 34%). MS (M+H)+=278.5.

1. temperatureat reflux for 2 hours
2. concentrationconcentrated
3. washThe solution was washed with brine 3×
4. dry with materialdried (MgSO4)
5. concentrationconcentrated
6. washColumn chromatography eluting with 50% EtOAc/hexanes