4-Carboxymethoxy-3-methyl-benzoic Acid Methyl Ester → 4-{2-[4-(3,3-Dimethyl-butyl)-piperazin-1-yl]-2-oxo-ethoxy}-3-methyl-benzoic Acid Methyl Ester

Participants

Reaction Steps

WSCD (5.14 g, 27.2 mmol) and DMAP (1.64 g, 13.6 mmol) were added to a solution of 4-carboxymethoxy-3-methyl-benzoic acid methyl ester from Example E41.2 (3.04 g, 13.6 mmol) in dichloromethane (100 ml) and triethylamine (5 ml). The mixture was stirred for 1 h at room temperature then 1-(3,3-dimethyl-butyl)-piperazine dihydro-chloride from Example E4 (3.67 g, 14.9 mmol) was added. The mixture was stirred for 20 h at room temperature then solvents were removed in vacuo. The residue was dissolved in EtOAc, washed with saturated NaHCO3 then brine, dried and concentrated in vacuo. The residue was purified by flash chromatography on silica gel (eluant; EtOAc) to yield the title compound (2.8 g, 55%).

Provenance & Evidence