Syntheses, characterization, and single crystal X-ray analysis of 2-pyridyl aryl selenium (IV) bromides and chlorides

Abstract

In the present work, a variety of symmetrical and unsymmetrical 2-pyridyl aryl selenium (IV) chlorides or bromides were prepared by the dropwise addition of a dilute solution of bromine or sulfuryl chloride to the corresponding 2-pyridyl aryl selenide in dried organic solvent with continuous stirring at 0 °C. Removal of the solvent under reduced pressure resulted in the synthesis of, 2-pyridyl aryl selenium (IV) bromides or chlorides, respectively, in quantitative yields. The titled dihalides prepared were characterized by elemental analysis, spectroscopic studies, and single crystal X-ray analysis. Single crystal X-ray analysis revealed that the 2-pyridyl aryl selenium (IV) bromides/chlorides have a distorted trigonal bipyramidal structure. The pyridyl and phenyl rings along with a lone pair of electrons on selenium are at equatorial positions whereas chloride/bromide atoms at axial positions of the distorted trigonal bipyramidal structure.

Graphical Abstract

KEYWORDS:

• Pyridyl
• phenyl
• selenium
• sulfuryl chloride
• bromine
• chloroform

Acknowledgments

The authors are thankful to Department of Chemistry, Panjab University, Chandigarh for providing laboratory and library facilities to carry out this research work. We express special thanks to Prof. R.J. Butcher, Howard University, USA, Prof. Sanjay Mandel, IISER, Mohali and Prof. Saurav Chatterjee, NIT, Rourkela for X-ray crystallographic and ⁷⁷Se NMR spectral data.