Water → 2-(3,4-Diethoxyphenyl)-5-(pyridin-4-yl)-1,3,4-oxadiazole

To a stirred suspension of Na2CO3 (1.42 mmol, 150.52 mg) and pyridine-4-carbohydrazide (0.71 mmol, 97 mg) in NMP (0.8 mL) was added a solution of 3,4-diethoxybenzoylchloride (prepare above) in NMP (0.8 mL). The reaction was stirred for 12 h at room temperature, poured to 20 mL of cold H2O and filtered. The precipitated intermediate was dried in vacuo. The solid was added to POCl3 (5 mL) and heated to 70-72° C. for 6 h. The solution was poured in an ice-water container and neutralized with a solution of NaOH (2M). The precipitated product was filtered and purified by C.C. using CH2Cl2:MeOH (9:1) to yield the product in 67% yield (150 mg).

1. filtrationfiltered
2. customThe precipitated intermediate was dried in vacuo
3. additionThe solid was added to POCl3 (5 mL)
4. temperatureheated to 70-72° C. for 6 h
5. additionThe solution was poured in an ice-water container
6. filtrationThe precipitated product was filtered
7. custompurified by C.C
8. customusing CH2Cl2:MeOH (9:1) to yield the product in 67% yield (150 mg)

ORD-Eintrag

ord-a7ed30250e464e69956d3c054b1fee28

Quelldatensatz

uspto-grants-2013_09

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08530503B2