p-Toluenesulfonic acid → N-benzyl-1-(2-bromoacetyl)cyclopentanecarboxamide

Participants

Reaction Steps

To a solution of 1-acetyl-N-benzylcyclopentane carboxamide (44 g, 179.36 mmol) in EtOH (700 mL) were added NBS (70.22 g, 394.59 mmol) and PTSA (3.5 g, 17.94 mmol). After addition, the reaction mixture was stirred at rt for 48 h and concentrated in vacuo. To the residue was added water (500 mL) and the resulting mixture was extracted with EtOAc (500 mL×3). Then the combined organic phases were washed with saturated Na2S2O3 solution (500 mL×3) and brine (500 mL), dried over anhydrous Na2SO4, then filtered and concentrated in vacuo. The residue was purified by silica gel column chromatography (EtOAc/PE (v/v)=1/5) to give the product as a white solid (39.5 g, 68%).

Provenance & Evidence