6-BROMO-2,4-DICHLOROBENZO[D]THIAZOLE synthesis

Yield:1188053-85-1 51.4%

Reaction Conditions:

with copper dichloride;isopentyl nitrite in acetonitrile at 20 - 60; for 2.16667 h;

Steps:

22

To a suspension of copper chloride (II) (1.78 g, 13.20 mmol) in acetonitrile (29 ml) was added under ice-cooling and nitrogen atmosphere isopentyl nitrate (2.22 ml, 16.51 mmol). To the mixture was added for 10 minutes 2-amino-6-bromo-4-chlorobenzo[d]thiazole 61 (2.90 g, 11.00 mmol). It was stirred at room temperature for 10 minutes. The mixture was heated at 60 °C for 2 hours. After the end of the reaction, 2N HCl was added to the mixture. The mixture was extracted with ethyl acetate. The organic layer was washed with water and brine, respectively and dried over sodium sulfates. The solvent was evaporated under reduced pressure. The residue was purified with column chromatography (n-hexane : ethyl acetate = 4 : 1) to give Compound 62 (1.60 g, yield 51.4%). ¹H-NMR(DMSO-d₆) δ: 7.93 (d, J=1.8 Hz, 1H), 8.40 (d, J=1.8 Hz, 1H).

References:

EP2351744,2011,A1 Location in patent:Page/Page column 71