Chloromethyl Methyl Ether → 2-Methoxy-5-(methoxymethoxy)pyridine

To a solution of 6-methoxypyridin-3-ol (20 g, 0.16 mol) in DMF (200 mL) was added NaH (60% in mineral oil; 9.6 g, 0.24 mol) at 0-5° C. portion-wise. Upon the completion of addition, the mixture was continued to stir at 0-5° C. for 15 min followed by additional of chloromethyl methyl ether. The mixture was stirred at 0-5° C. for another 20 min and quenched with aqueous NH4Cl(sat). The aqueous layer was extracted with EtOAc (3×100 mL) and the combined organic layer was washed with water and brine, dried over Na2SO4, and concentrated under reduced pressure. The residue was purified on silica gel with 25% EtOAc/hexanes as eluent to give 2-methoxy-5-(methoxymethoxy)pyridine (24.1 g, 89.3%) as a colorless oil. 1H NMR (400 MHz; CDCl3) 7.97 (d, 1H), 7.35 (dd, 1H), 6.70 (d, 1H), 5.12 (s, 2H), 3.91 (s, 3H), 3.51 (s, 3H); MS (ESI) m/z 170.1 [M+H]+.