Hydrochloric Acid → Methyl 2-(2,4-difluorobenzyl)isonicotinate

Participants

Reaction Conditions

Reaction Steps

Methyl 2-chloroisonicotinate (5.2 g, 30.31 mmol) and Pd(PPh3)4 (0.700 g, 0.61 mmol) were dissolved in THF (100 mL) under nitrogen and (2,4-difluorobenzyl)zinc(II) chloride (0.5 M in THF, 90 mL, 45.00 mmol) was added and the brown solution was stirred at 60° C. overnight (18 h). The reaction was quenched by addition of methanol (50.0 mL). The solution was diluted with EtOAc and washed with NH4Cl (aq) and brine and dried over Na2SO4 to give a red oil. The crude was redissolved in MTBE (200 mL) and solids were filtered off. Hydrogen chloride (4 M in dioxane, 7.58 mL, 30.31 mmol) was added dropwise during stirring and a suspension was formed. The suspension was stirred at room temperature for 15 min. The solid was collected by filtration and washed with MTBE. The solid was dissolved in MTBE/satd NaHCO3. The phases were separated, the organic phase dried over Na2SO4, filtered and evaporated to yield methyl 2-(2,4-difluorobenzyl)isonicotinate (7.011 g, 88%) as a red oil. 1H NMR (400 MHz, cdcl3) δ 3.93 (s, 3H), 4.20 (s, 2H), 6.77-6.88 (m, 2H), 7.18-7.25 (m, 1H), 7.62-7.73 (m, 2H), 8.69 (dd, 1H). MS m/z 264 (M+H)+

Provenance & Evidence