4-[2-(Toluene-4-sulfonyloxymethyl)furan-3-yl]piperidine-1-carboxylic acid t-butyl ester (65 mg, 0.15 mmol was dissolved in MeCN (770 μL) and added to a mixture of potassium carbonate (32 mg, 230 mmol, 1.6 eq.) and 3-chlorophenol (28.8 mg, 224 μmol, 1.5 eq.). The resulting mixture was shaken at 50° C. overnight. The mixture was then cooled and the solids removed. The supernatant was combined with TFA (12 μL, 160 mmol, 1.0 eq.) and the resulting mixture was shaken overnight at room temperature. The solution was concentrated using an evaporator, then dissolved in 1:1 AcOH:H2O (5.0 mL) then an additional 2.0 ml AcOH, filtered, and purified by preparative HPLC to yield the title compound as a TFA salt (4.3 mg, 98% purity). MS m/z: [M+H]+ calcd for C16H18ClNO2, 292.10. found 292.0.
