Biaryl thioether synthesis via CuI catalyzed dominothiolation of aryl halides in the presence of DMAP as ligand

- A faster method for the synthesis of biaryl thioethers from aryl halides.
- Use of DMAP as ligand for CuI catalyzed C-S cross coupling reaction.
- Significant rate acceleration of CuI catalyzed process by DMAP.
- Applicable to different kinds of aryl iodides and bromides.
- The product yields are high.

An improved protocol has been developed for the synthesis of symmetrical biaryl sulfides via a dominothiolation reaction using CuI as catalyst in the presence of DMAP as ligand. The coupling reaction of aryl halides was carried out in the presence of 5 mol % of CuI and 20 mol % of DMAP using thiourea as sulfur transfer agent. High yields of corresponding product were obtained by carrying out the reaction in DMSO at 120 °C.