Synthesis
The general procedure for the synthesis of 6-chlorobenzothiazole from 2-amino-6-chlorobenzothiazole was as follows: 0.3 mmol of 2-amino-6-chlorobenzothiazole, 0.6 mmol of sodium nitrite, and 3 mL of 1,2-dichloroethane were added to a closed reaction vessel. The reaction mixture was stirred at 110°C for 60 hours. After completion of the reaction, the mixture was cooled to room temperature, diluted with 10 mL of dichloromethane and subsequently filtered. The solvent was removed by distillation under reduced pressure and the resulting residue was purified by column chromatography with an eluent ratio of V (petroleum ether)/V (ethyl acetate) = 6/1 to give the final 6-chlorobenzothiazole in 89% yield.
References
[1] Chemical and Pharmaceutical Bulletin, 1998, vol. 46, # 4, p. 623 - 630
[2] Patent: CN105367442, 2016, A. Location in patent: Paragraph 0018
[3] Chemical and Pharmaceutical Bulletin, 1997, vol. 45, # 9, p. 1547 - 1549
[4] Tetrahedron, 2013, vol. 69, # 22, p. 4436 - 4444
[5] Synthetic Communications, 1980, vol. 10, # 3, p. 167 - 174
