Yield:161417-28-3 89%

Reaction Conditions:

with sodium methylate in methanol

Steps:

20.c 20c.
20c. 4-bromo-3-pyridinol To a solution of 4bromo-3-pyridyl diethylcarbamate (1.24 g, 4.50 mmol) in methanol (10 mL) was added sodium methoxide in methanol (2.04 g, 9.40 mmol), and the resultant mixture was refluxed for 1.5 hours. After removal of MeOH, EtOAc (15 mL) and water (1 mL) were added, the pH was then adjusted to 9 using 20% H₂ SO₄. The organic layer was decanted, and the residue washed with EtOAc (3*5 mL). The combined organic layers were dried (Na₂ SO₄) and concentrated. The crude product was purified by flash chromatography on silica gel eluding with hexane/EtOAc (1:1 and 1:2) to provide 691 mg (89% yield) of the title compound. TLC R_f 0.38 (1:2 hexane/EtOAc). MS (DCI/NH₃) m/e 174 with ⁷⁹ Br and 176 (M+H)⁺ with ⁸¹ Br. ¹ H NMR (CDCl₃, 300 MHz) δ: 8.43 (d, J =1.5 Hz, 1H, ArH), 8.02 (d, J=7.2 Hz, 1H, ArH), 7.54 (dd, J=7.2, 1.5 Hz, 1H, ArH).

References:

Abbott Laboratories US5914328, 1999, A

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