Cyclopentanol → (S)-(4-Nitro-benzenesulfonylamino)-phenyl-acetic acid cyclopentyl ester

Participants

Reaction Conditions

Reaction Steps

To a solution of stage 1 acid (4.32 g, 12.8 mmol) in cyclopentanol (60 ml) at 0° C. was added slowly thionyl chloride (9.3 ml, 128 mmol). The reaction mixture was stirred and heated under reflux at 70° C. for 2 hours. The excess thionyl chloride was removed by evaporation in vacuo, the reaction mixture was extracted into EtOAc and washed with saturated NaHCO3 solution and dried over Na2SO4, filtered and evaporated to dryness. Flash column chromatography purification with DCM gave the required product (3.6 g, 70% yield). LCMS purity of 100%, (molecular ion not observed).

Provenance & Evidence