Water → 6-Bromo-2-chlorothiazolo[4,5-b]pyridine hydrochloride

Participants

Reaction Steps

A solution of 3,5-dibromopyridine-2-amine (5 g, 19.85 mmol) and potassium O-ethyl carbonodithioate (7.64 g, 47.6 mmol) in DMF (25.6 mL) was heated to 130° C. where it stirred overnight. After this time, the reaction mixture was allowed to cool to rt. Once at the prescribed temperature, the reaction mixture was diluted with HCl (1 N, 150 mL), and then stirred at rt for an additional hour. At the conclusion of this period, the resulting solid was collected by filtration, washed with water (2×15 mL), and then air-dried. The resulting material was suspended in CH2Cl2 (26 mL) and sulfuryl chloride (17.1 mL, 210 mmol) was slowly added. After 2 hr, water (50 mL) was slowly added to decompose the excess sulfuryl chloride (cooled to 0° C.). The resulting precipitate was collected by filtration and dried to afford Compound 21A as a light yellow solid (5.6 g, 99% yield). 1H NMR (400 MHz, DMSO-d6) δ ppm 8.88 (d, J=2.2 Hz, 1H), 8.79 (d, J=2.2 Hz, 1H). LC/MS (m/z)=250 (M+H)+.

Provenance & Evidence