methyl (S)-lactate → methyl 2-(R)-{[-4-(4-chlorophenyl)piperazine-1-sulfonyl]amino}propionate

Participants

Reaction Conditions

Reaction Steps

A solution of potassium tert-butoxide (0.87 ml, 1M in tetrahydrofuran) was added to a solution of [4-(4-chlorophenyl)piperazine-1-sulfonyl]amine (200 mg, 0.73 mmol), [prepared as described in Step 1 above], in tetrahydrofuran (10 ml) at −60° C. After 10 min., a solution of the triflate derivative of methyl (S)-lactate (604 mg, 2.56 mmol) in tetrahydrofuran (3 ml) was added and the reaction mixture was allowed to warm to −30° C. over 30 min. The reaction mixture was quenched with saturated ammonium chloride and the product was extracted into ethyl acetate. The solvent was removed in vacuo and the residue was chromatographed (SiO2, 30% ethyl acetate/hexane) to give methyl 2-(R)-{[4-(4-chlorophenyl)piperazine-1-sulfonyl]-amino}propionate as a colorless oil (66%).

Provenance & Evidence