KOBu-Promoted Halogen-Bond-Assisted Intramolecular C-S Cross-Coupling of -Iodothioanilides for the Synthesis of 2-Substituted Benzothiazoles.

An efficacious and mild KOBu-promoted intramolecular C-S cross-coupling of -iodothioanilides in conjunction with a catalytic quantity of phenanthroline as an additive has been described for the convenient synthesis of 2-substituted benzothiazoles. The methodology is suitable for attaining a wide variety of 2-alkyl- and 2-aryl-substituted benzothiazoles. Single-crystal XRD, DFT calculations, NMR, and UV studies suggest that halogen bonds between the units of -iodothioanilides may assist in the electron transfer process.