Thiophosphoryl-, Thiophosphoryloxy-, and Thiophosphorylamino-Benzene Derivatives as Novel Classes of Hybrid Pincer Ligands

Abstract

The synthetic approaches to novel families of SCE (E = S′,N,O) hybrid pincer-type ligands bearing thophosphoryl, thiophosphoryloxy, and thiophosphorylamino groups in various combinations with thiophosphoryl-, thiocarbamoyl-, and imine- (including that of benzothiazole ring) donating functions have been developed. All of the ligands readily undergo direct cyclometallation (metal = Pd(II), Pt(II)) to afford 5,5- or 5,6-membered pincer complexes. Palladium complexes displayed from high to excellent catalytic performance in the Suzuki cross-coupling reaction of aryl bromides and phenylboronic acid and the higher asymmetry for a complex served as a factor of its higher catalytic activity.

Keywords:

• Catalysis
• palladium
• pincer complexes
• pincer ligands
• platinum
• Suzuki cross-сoupling
• thiophosphoryl compounds

Acknowledgments

The authors are grateful to the Russian Basic Research Foundation (grant 08-03-00508) for financial support.