反应详情

温度

5 °C

Lithium borohydride (207 mL, 414.0 mmol, 2M in THF) was added to a stirred solution of 1-(4-methoxy-benzoyl)-pyrrolidine-3,3-dicarboxylic acid ethyl ester (88.63 g, 275.8 mmol) (see Preparation 8) in isopropyl alcohol (600 mL) at 5° C. The mixture was stirred for 4 hours at 5° C. then quenched with 2M HCl aqueous solution (300 mL) and stirred for 15 minutes. The solvent volume was reduced by concentration under reduced pressure and the aqueous residue was extracted with ethyl acetate (300 mL). The organic layer was separated, washed with water (300 mL) then concentrated under reduced pressure to afford a pale brown solid. This was triturated with acetonitrile to afford the title compound as a white solid (27.8 g, 36%). (99.3:0.7 ratio of isomers)

1. customthen quenched with 2M HCl aqueous solution (300 mL)
2. stirringstirred for 15 minutes
3. concentrationThe solvent volume was reduced by concentration under reduced pressure
4. extractionthe aqueous residue was extracted with ethyl acetate (300 mL)
5. customThe organic layer was separated
6. washwashed with water (300 mL)
7. concentrationthen concentrated under reduced pressure
8. customto afford a pale brown solid
9. customThis was triturated with acetonitrile