Hofmannl obtained benzothiazoles by the action of acids, acid chlorides and acid anhydrides upon o-aminothiophenol. Upon condensing certain aldehydes with o- aminothiophenol, he also obtained benzothiazoles.* He formulated the change as involving two molecules of aldehyde, one of which was reduced to the alcohol in the process.
![5-CHLOROBENZO[D]THIAZOLE Structure](https://image.chemsrc.com/caspic/125/2786-51-8.png)
