Methyl Bromide → HCID 16720334, compound

0.22 ml of 1.0 M NaHMDS solution in THF (0.22 mmol) was added to 0.5 ml of THF solution containing 80 mg 3-(2-oxo-1,2,5,6-tetrahydro-pyridin-3-yl)-propionic acid methyl ester (f) prepared from the step 1 in Example 3 (0.44 mmol) in a dropwise manner at −79° C. and then stirred for 30 min. After 0.48 ml of methyl bromide (0.48 mmol) was added to the reaction mixture, the solution was stirred at 0° C. for 3 hrs. The reaction mixture was quenched by 2 ml of sat. NH4Cl solution and then the organic layer was extracted with ethyl acetate (7 ml). The combined organic layer was washed with 2 ml of sat. NH4Cl solution (2 ml) and 2 ml of sat. NaCl solution subsequently. Then the organic layer was dried over anhydrous MgSO4, filtered and concentrated in vacuo. The resulting compound was purified by column chromatography on Silica gel with EtOAc solvent as an eluant to give 62 mg (yield: 72%) of the title compound (i2).