Sodium Bicarbonate → 2-Oxo-1-(1-benzylpiperidin-4-yl)-2,3-dihydro-1H-imidazo[4,5-b]pyrazine

Temperatur

180 °C

3-[(1-Benzylpiperidin-4-yl)amino]pyrazine-2-carbohydrazide (3.0 g, 9.2 mmol) was dissolved in 1N HCl (20 mL) and water (40 mL), and cooled to 0° C. To this was added aqueous sodium nitrite (0.8 g, 11.6 mmol) in water (5 mL). After 0.5 h sodium bicarbonate was added and the basic solution extracted with chloroform (5×50 mL), which was dried over magnesium sulfate. The crude acyl azide was dissolved in methoxyethanol (20 mL) and heated at 180° C. for 3 h. The progress of the reaction was monitored by thin layer chromatography (10% methanol in chloroform). The reaction was cooled and concentrated, and the crude product purified by preparative thin layer chromatography (silica gel, 75:25 tetrahydrofuran:hexane) to give the title compound (1.7 g). MS 310 (M+1).

1. extractionthe basic solution extracted with chloroform (5×50 mL), which
2. dry with materialwas dried over magnesium sulfate
3. dissolutionThe crude acyl azide was dissolved in methoxyethanol (20 mL)
4. temperatureThe reaction was cooled
5. concentrationconcentrated
6. customthe crude product purified by preparative thin layer chromatography (silica gel, 75:25 tetrahydrofuran:hexane)

ORD-Eintrag

ord-076fd3cbd9e54fe2bd2326e13107d90a

Quelldatensatz

uspto-grants-2008_11

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07452903B2