Methyl iodide → HCID 66773582, compound

Participants

Reaction Conditions

Reaction Steps

To a cooled (−78° C.) solution of diisopropylamine (0.032 mol) in dry THF (15 mL), n-BuLi (0.030 mol) was added dropwise under argon atmosphere, and the reaction was stirred for 30 min at −78° C., then for one hour at −20° C. The resulting LDA solution was transferred to the solution of the known compound (R)-4-benzyloxy-pyrrolidine-1,2-dicarboxylic acid 1-tert-butyl ester (CAS: 54631-81-1, e.g. Tetrahedron, 42(21), 6039-45; 1986) (3.5 g, 0.011 mol) in THF (15 mL) at −78° C., and the mixture was stirred for 30 minutes at −78° C., then at 0° C. for one hour. The reaction mixture was once again cooled to −78° C. and methyl iodide (0.82 mL, 0.013 mol) was added to it over 10 min and stirred the reaction mixture was stirred at 0° C. then at rt for one hour. After completion of the reaction by TLC, the reaction mixture was quenched with 1N HCl (20 mL) and extracted with DCM. The organic layer was concentrated under reduced pressure to give a crude material, which was purified through column chromatography (10-20% ethyl acetate:hexane, basic alumina, diameter of column—2.5 cm, height of alumina—approx. 7 inch) to afford the desired (rac)-4-benzyloxy-2-methyl-pyrrolidine-1,2-dicarboxylic acid 1-tert-butyl ester 800 mg (22%) as a white solid.

Provenance & Evidence