To a solution of 3-(azidomethyl)-7-methylquinoline (46.0 mg, 0.232 mmol) and tert-butyl (4,6-dimethyl-5-(propionamidomethyl)pyridin-2-yl)carbamate (70 mg, 0.231 mmol) in t-BuOH (1.8 ml)/water (1.8 ml) were added copper(II) sulfate pentahydrate (11.52 mg, 0.046 mmol) and sodium ascorbate (45.7 mg, 0.231 mmol). Reaction mixture was stirred overnight at 23° C. Reaction mixture was poured into water and extracted twice with ethyl acetate. Combined organic layers were washed with brine, dried over sodium sulfate and evaporated to afford a crude product, which was purified by silica gel chromatography (cyclohexane/ethyl acetate from 100/0 to 0/100) to afford the title compound. HPLC (Method G) Rt=1.408 min, MS (Method V) [M+H]+=502.4.
