Elemental sulfur mediated cyclization via redox strategy: Synthesis of benzothiazoles from o-chloronitrobenzenes and benzyl chlorides
A novel metal-free synthesis of 2-substituted benzothiazoles from easily available o-chloronitrobenzenes and benzyl chlorides using elemental sulfur as traceless oxidizing agent has been developed. The protocol provides a simple, efficient, and atom-economic way to access to benzothiazoles in moderate to excellent yields. And the approach exhibited good functional group tolerance.
One-pot copper-catalyzed synthesis of 2-substituted benzothiazoles from 2-iodoanilines, benzyl chlorides and elemental sulfur
An efficient one-pot three-component reaction of 2-iodoanilines, benzyl chlorides and elemental sulfur to form 2-substituted benzothiazoles in satisfactory yields (up to 98%) has been described. The reaction tolerated a wide range of functional groups on the aromatic ring. And heterocycle methylene chlorides substrates were also found to be compatible.