Chlorosulfonic acid → 2,4-Dibromothiazole-5-sulfonyl chloride

To a flask containing chlorosulfonic acid (51.0 mL, 767 mmol) was added 2,4-dibromothiazole (10.2 g, 42.0 mmol) with stirring over 15 minutes. The resulting solution was heated to 150 degrees overnight. The reaction was quenched by carefully and slowly pouring onto ice (500 mL). The resulting precipitate was extracted with ethyl acetate (2×200 mL) and the combined organic layers were washed with water, dried, and concentrated in vacuo. The residue was purified by silica gel chromatography (ethyl acetate/hexane=0/100→15/85) to give 8.1 g (56% yield) of the title compound as a yellow oil which partially solidified. 13C NMR (400 MHz, CDCl3) δ: 145.04, 138.78, 131.81.

1. temperatureThe resulting solution was heated to 150 degrees overnight
2. customThe reaction was quenched by carefully and
3. additionslowly pouring onto ice (500 mL)
4. extractionThe resulting precipitate was extracted with ethyl acetate (2×200 mL)
5. washthe combined organic layers were washed with water
6. customdried
7. concentrationconcentrated in vacuo
8. customThe residue was purified by silica gel chromatography (ethyl acetate/hexane=0/100→15/85)

ORD record

ord-d982510a8d8340efb561c1087f216c89

Source dataset

uspto-grants-2014_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08796271B2