Methanol → tert-butyl (2R)-2-ethynylpyrrolidine-1-carboxylate

Participants

Reaction Steps

Butyl lithium (48 mL, 0.08 mol) was added at -78° C. to a stirred solution of (R)-t-butyl 2-(2,2-dibromoethenyl)-1-pyrrolidinecarboxylate (14.2 g, 0.04 mol) in dry THF (300 mL). The color turned to dark yellow. After 15 min. methanol (10 mL) and ethyl acetate (10 mL) were added and the solution was allowed to warm to room temperature. The solvent was removed and the residue was partitioned between ethyl acetate and water. The ethyl acetate phase was concentrated and applied to a silica gel column. Elution with ethyl acetate:Skellysolve B (1:10) gave 6.9 g (88%) of product as a yellow oil.

Provenance & Evidence