ETHYL 7-BROMO-4-HYDROXYPYRROLO[2,1-F][1,2,4]TRIAZINE-5-CARBOXYLATE synthesis

Yield:938192-22-4 92%

Reaction Conditions:

with N-Bromosuccinimide;trifluoroacetic acid in dichloromethane at 20; for 2 h;

Steps:

1.1B

IB: Ethyl 7-bromo-4-hydroxypyrrolo[l,2-fJ [1 ,2,4]triazine-5-carboxylate[00126] 1A (2.072 g, 10 mmol) was suspended in dichloromethane (15 mL) and treated with TFA (0.3 mL). To this suspension was added NBS (1.87 g, 10.5 mmol) and the reaction mixture was stirred for 2 h at ambient temperature. The mixture was then concentrated under reduced pressure and the crude product was suspended in THF-hexanes. The reaction mixture was filtered, rinsed several times with water and once with ether, and air-dried briefly to afford a solid. Brief evacuation (high-vac. line) served to remove traces of solvent, providing IB (2.62 g, 92% yield) as a colorless solid. MS (ES): m/z= 288 [M+H]⁺. NMR (400 MHz, DMSO-d₆) δ ppm 1.28(t, 3 ? J = 7.2 Hz); 4.00-4.48(m, 2 H); 7.09(s, 1 H) 8.08(s, 1 H); 12.14(s, 1 H).

References:

WO2011/123493,2011,A1 Location in patent:Page/Page column 45