Tetrahydrofuran → 2-Fluoro-5-(1,3-thiazol-2-yl)pyridine

Participants

Reaction Steps

To a 7 mL dram vial equipped with a stir bar was added 5-bromo-2-fluoropyridine (500 mg, 2.84 mmol) and Pd(dppf)Cl2 (104 mg, 0.142 mmol). The vial was sealed with a septum cap and then placed under N2 atm. To the vial was added thiazol-2-ylzinc(II) bromide in THF (6 mL, 3.00 mmol). The vial was placed in a 65° C. heating block with stirring for 2.5 h. The reaction solution was transfered to a 125 mL separatory funnel and was diluted with sat. aq. NaHCO3 (50 mL) upon which a significant amount of a white solid precipitated. The mixture was extracted with EtOAc (2×50 mL). The combined organics were washed with brine (50 mL); dried over MgSO4; filtered; then concentrated in vacuo. The resulting was subjected to silica gel chromatography (hexanes:EtOAc) to afford 2-(6-fluoropyridin-3-yl)thiazole as a white solid, 303 mg (59%). 1H-NMR (500 MHz, CDCl3) δ 8.80 (d, J=2.5 Hz, 1H), 8.39 (ddd, J=8.5, 7.4, 2.5 Hz, 1H), 7.92 (d, J=3.3 Hz, 1H), 7.42 (d, J=3.3 Hz, 1H), 7.07-7.03 (m, 1H).

Provenance & Evidence