Uses
6-Chloro-3-pyridinesulfonyl Chloride, is a heterocylic building block used for chemical synthesis. It is also an intermediate in the synthesis of 6-Aminopyridine-3-sulfonamide (A628835), that can be used as anticoccidial agents.
Synthesis
General procedure for the synthesis of 2-chloropyridine-5-sulfonyl chloride from 2-chloro-5-aminopyridine: 10 g (79.2 mmol) of 2-chloro-5-aminopyridine was dissolved in a mixture of concentrated hydrochloric acid (16 mL) and glacial acetic acid (89 mL), and cooled to 10 °C in an ice bath. 5.46 g (79.2 mmol) of sodium nitrite was added in batches and the reaction temperature was controlled to be below 15 °C. After stirring the reaction mixture for 1 hour, it was slowly added dropwise to a solution containing sulfur dioxide (carrier 27 mL), 2.77 g (16.2 mmol) of sulfur dioxide, copper(II) chloride dihydrate, and a solution consisting of acetic acid (59 mL) and water (11 mL), with the dropwise addition time being controlled to be between 5 and 10 minutes. The reaction mixture was gradually warmed to room temperature and subsequently poured into an ice-water mixture (300 mL) and stirring was continued for 15 minutes. The precipitate was isolated by filtration, washed with water (2 x 100 mL) and dried under reduced pressure to give 12.99 g of 2-chloropyridine-5-sulfonyl chloride. The product was characterized by 1H NMR (400 MHz, chloroform-d): δ 7.62 (1H, d, J = 8.31 Hz), 8.26 (1H, dd, J = 8.56,2.69 Hz), 9.04 (1H, d, J = 2.69 Hz).
References
[1] Patent: US2008/39464, 2008, A1. Location in patent: Page/Page column 30-31
[2] Organic Process Research and Development, 2009, vol. 13, # 5, p. 875 - 879
[3] Bioorganic and Medicinal Chemistry Letters, 2013, vol. 23, # 13, p. 3947 - 3953
[4] Patent: WO2009/39328, 2009, A1. Location in patent: Page/Page column 54
[5] Patent: EP1144368, 2004, B1. Location in patent: Page 64