Phosphorus oxychloride → 5,7-Dichlorothieno[2,3-c]pyridine

Temperature

115 °C

A mixture of 7-chlorothieno[2,3-c]pyridine 6-oxide (2.58 g, 13.8 mmol) and POCl3 (20 mL) was stirred at 115° C. under N2 for 7 h. After that time, the excess POCl3 was removed in vacuo, and the residue was poured into ice/water (100 mL), basified by addition of 8 N NaOH followed by saturated NaHCO3, and extracted with DCM (3×50 mL). The combined extracts were washed with saturated NaHCO3 (50 mL), water (50 mL) and brine (50 mL), dried over MgSO4, and concentrated in vacuo. The residue was purified by ISCO chromatography (0 to 40% EtOAc:heptane) to afford 1.97 g (70%) of the title compound as a beige solid. 1H NMR (400 MHz, DMSO-d6): δ 7.82 (d, J=5.6 Hz, 1 H), 7.68 (s, 1 H), 7.37 (d, J=5.6 Hz, 1 H); MS (ESI): 203.94, 205.94 [M+H]+; HPLC tR=1.55 min (TOF: polar—3 min).

1. customAfter that time, the excess POCl3 was removed in vacuo
2. additionthe residue was poured into ice/water (100 mL)
3. additionbasified by addition of 8 N NaOH
4. extractionextracted with DCM (3×50 mL)
5. washThe combined extracts were washed with saturated NaHCO3 (50 mL), water (50 mL) and brine (50 mL)
6. dry with materialdried over MgSO4
7. concentrationconcentrated in vacuo
8. customThe residue was purified by ISCO chromatography (0 to 40% EtOAc:heptane)

ORD record

ord-6ab90584bfaf45d7ba7cb8f375c0eef3

Source dataset

uspto-grants-2013_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08378104B2