7-Chlorothieno[3,2-b]pyridine

Uses

7-Chlorothieno[3,2-b]pyridine is a pyridine derivative and a pharmaceutical intermediate compound. It can be used in the preparation of piperidines and deuterated thiophene pyridine compounds, and can also be used in the synthesis of compounds with anticancer activity.

Chemical Properties

7-Chlorothieno[3,2-b]pyridine is a white to yellow to orange powder to lumpy intermediate composition. It has a melting point of 35 °C and a flash point of 110 °C. It is stored at 0-10 °C. It is irritating to eyes and skin.

Synthesis

To a 250 mL round-bottomed flask were added 30 mL of methylene chloride and 20 mL of ethylene chloride, followed by N,N-dimethylformamide (1.8 mL, 23.28 mmol) and oxalyl chloride (2.9 mL, 33.86 mmol). Oxalyl chloride was slowly added dropwise to the mixture at 0 °C. Next, thieno[3,2-b]pyridin-7(4H)-one (1.6 g, 10.58 mmol) was added and the reaction mixture was heated to reflux for 6 hours. After completion of the reaction, the mixture was cooled to room temperature to afford 7-chlorothieno[3,2-b]pyridine (1.7 g, 90% yield) as a pale yellow solid. The product was characterized by 1H-NMR (400 MHz, CDCl3): δ 8.61 (d, J = 5.2 Hz, 1H), 7.81 (d, J = 5.2 Hz, 1H), 7.30 (d, J = 4.8 Hz, 1H).

References

[1] Patent: US2013/72482, 2013, A1. Location in patent: Paragraph 0281; 0286; 0287
[2] Patent: EP1724268, 2006, A1. Location in patent: Page/Page column 50-51
[3] Bioorganic and Medicinal Chemistry Letters, 2004, vol. 14, # 1, p. 21 - 24
[4] Patent: CN107151240, 2017, A. Location in patent: Paragraph 0262; 0263; 0264
[5] Journal of Chemical Research, Miniprint, 1984, # 3, p. 771 - 795