反应详情

To a stirred solution of (R)-2-benzyl-pyrrolidine-1,2-dicarboxylic acid 1-tert-butyl ester (1.23 g, 4.0 mmol) in THF (10 mL) and methanol (10 mL) at 0° C. under nitrogen was added TMS-diazomethane (5.0 mL of a 2.0 M solution in hexanes, 5.0 mmol) dropwise. The reaction mixture was warmed to ambient temperature then concentrated in vacuo to an oil (1.36 g). Purification by chromatography (silica, 5-15% EtOAc in hexanes) gave (R)-2-benzyl-pyrrolidine-1,2-dicarboxylic acid 1-tert-butyl ester 2-methyl ester (1.03 g, 3.23 mmol, 81%) as an oil.

1. concentrationthen concentrated in vacuo to an oil (1.36 g)
2. customPurification by chromatography (silica, 5-15% EtOAc in hexanes)