反应详情

To a solution of tert-butyl 2,5-dihydro-1H-pyrrole-1-carboxylate (10.0 g, 59.1 mmol) and Rh(OAc)2 (500 mg) in CH2Cl2 (200 mL) was added a solution of ethyl diazoacetate (8.14 g, 71.5 mmol) in CH2Cl2 (80 mL) over 12 h with a syringe pump. The reaction was filtered through celite, concentrated under vacuum and purified by column chromatography (silica gel) using 0 to 45% EtOAc in hexanes to afford ester 1 (6.70 g, 44%) as a clear straw colored oil; 1H-nmr (400 MHz, CDCl3) δ 4.18-4.03 (m, 2H), 3.71-3.53 (m, 2H), 3.39 (s, 2H), 2.04 (s, 2H), 1.42 (s, 9H), 1.28-1.19 (m, 3H).

1. filtrationThe reaction was filtered through celite
2. concentrationconcentrated under vacuum
3. custompurified by column chromatography (silica gel)