tert-butyl 2-(isopropoxycarbonyl)-5-bromopyridin-3-ylmethylcarbamate synthesis

Yield:863444-54-6 100%

Reaction Conditions:

with sodium hydride in tetrahydrofuran;N,N-dimethyl-formamide at 9 - 20; for 1.25 h;

Steps:

NaH (60%, 13.9 g, 347 mmol) was added at 7 portions to a solution of compound B-4 (104 g, 289 mmol) in THF / DMF (416 mL / 623 mL) at 9°C under N₂ atmosphere. After MeI (27 ml, 434 mmol) was added dropwise to the mixture, the reaction mixture was stirred at rt for 75 min. The resulting mixture was treated with NH₄Cl solution, extracted twice with EtOAc. The extract was washed with water and brine, dried over Na₂SO₄, and then the solvent was concentrated in vacuo to give 116 g of compound B-5 (quant) as a red oil. EPO ¹H NMR (CDCl₃) δ 8.64(1H, s), 7.76(1H, s), 5.29-5.23(1H, m), 3.23(3H₅ s), 1.39(6H, d, J = 6.3 Hz), 1.34(9H, s).

References:

WO2007/19098,2007,A2 Location in patent:Page/Page column 47-48