Ammonium Hydroxide → 7-Chlorothieno[3,2-b]pyridine

Temperature

105 °C

A suspension of thieno[3,2-b]pyridin-7-ol (4.6 g, 30.4 mmol) in POCl3 (15 mL, 30.4 mmol) was refluxed at 105° C. for 4 hr. The solvent was evaporated to afford a dark brown oil that was cooled in an ice bath and diluted with cold water. The aqueous layer was adjusted to a basic pH (˜8) by adding an NH4OH solution. The aqueous mixture was extracted with EtOAc and DCM. The combined organic layers were washed with brine, dried over Na2SO4, filtered, and concentrated to afford an oil. Purification of the crude material by silica gel chromatography using a BIOTAGE® machine (hexanes:ethyl acetate 75:25) afforded the title compound as a pale buff solid (4.7 g, 91%). ESI MS (M+H)+=170.0.

1. customThe solvent was evaporated
2. customto afford a dark brown oil that
3. temperaturewas cooled in an ice bath
4. extractionThe aqueous mixture was extracted with EtOAc and DCM
5. washThe combined organic layers were washed with brine
6. dry with materialdried over Na2SO4
7. filtrationfiltered
8. concentrationconcentrated
9. customto afford an oil
10. customPurification of the crude material by silica gel chromatography

ORD record

ord-6808fc9cb23d4857801a0fcad85785de

Source dataset

uspto-grants-2015_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08969586B2