Efficient synthesis of benzo[b]thiophenes from o-halophenyl acetonitrile has been achieved. This novel one-pot procedure involves CuI and pivalic acid catalyzed C–S bond formation using dithioesters followed by a heterocyclization reaction. This efficient protocol has the advantages of one-pot synthesis, short reaction time, good yields (62–78%) and operational simplicity.
![Graphical abstract: One-pot synthesis of 2,3-substituted benzo[b]thiophenes via Cu(i) catalysed intramolecular cyclisation from dithioesters](http://hg.y866.cn/compound/lib/scimg/usr/1/C5RA02114F.jpg)