Diisopropylethylamine → 4-amino-N-(6-chloropyridin-2-yl)-1,2,5-oxadiazole-3-carboxamide

Temperature

25 °C

A solution of 4-amino-1,2,5-oxadiazole-3-carboxylic acid (0.4 g, 3.1 mmol) and 6-chloropyridin-2-amine (0.56 g, 4.3 mmol) in N,N-dimethylformamide (6.2 mL) was treated with N,N,N′,N′-tetramethyl-O-(7-azabenzotriazol-1-yl)uronium hexafluorophosphate (1.4 g, 3.7 mmol) followed by N,N-diisopropylethylamine (0.76 mL, 4.3 mmol) at 0° C. The reaction mixture was stirred at 25° C. for 2 h, poured into saturated NaHCO3 (50 mL) and extracted with ethyl acetate (100 mL). The organic layer was separated and washed with brine (25 mL), dried with sodium sulfate, filtered, and concentrated to a crude solid. The crude solid was washed with ethyl acetate and filtered. The filtrate was concentrated and purified on silica gel to give the desired product with some impurities. The impurities were removed by washing the solid with chloroform to yield the desired product (65 mg, 9%). LCMS for C8H7ClN5O2 (M+H)+: m/z=240.1.

1. extractionextracted with ethyl acetate (100 mL)
2. customThe organic layer was separated
3. washwashed with brine (25 mL)
4. dry with materialdried with sodium sulfate
5. filtrationfiltered
6. concentrationconcentrated to a crude solid
7. washThe crude solid was washed with ethyl acetate
8. filtrationfiltered
9. concentrationThe filtrate was concentrated
10. custompurified on silica gel

ORD record

ord-f6d3c17003254f4097d6eb0e3f792084

Source dataset

uspto-grants-2014_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08846726B2