Imidazole-1-carboxylic acid 4-trifluoromethylbenzyl ester → 3-[3-(1-Ethoxycarbonyl-1-methyl-ethoxy)-4-methyl-phenyl]-piperidine-1-carboxylic acid 4-trifluoromethyl-benzyl ester

Participants

Reaction Steps

2-methyl-2-(2-methyl-5-piperidin-3-yl-phenoxy)-propionic acid ethyl ester L-tartaric acid salt (Example 11; 155 mg, 0.34 mmol) was dissolved in 50 mL ethyl acetate and washed with 50 mL saturated aqueous NaHCO3. The organic phase was dried over Na2SO4 and concentrated under reduced pressure. The resultant oil was taken up in 3 mL toluene and imidazole-1-carboxylic acid 4-trifluoromethyl-benzyl ester (92 mg, 0.34 mmol) was added. The reaction was stirred for 18 h at room temperature under nitrogen. The reaction was flash chromatographed with 15% ethyl acetate/hexanes to yield 157 mg (91%) of the desired 3-[3-(1-ethoxycarbonyl-1-methyl-ethoxy)-4-methyl-phenyl]-piperidine-1-carboxylic acid 4-trifluoromethyl-benzyl ester as a clear oil.

Provenance & Evidence