Studies on Some Thorium(IV) Complexes with High Coordination Numbers Derived from Semicarbazones of 4‐Aminoantipyrine

Abstract

The interaction of thorium(IV) salts with 4[N‐(benzylidene)amino]antipyrine semicarbazone (BAAPS), 4[N‐(4′‐methoxybenzylidene)amino]antipyrine semicarbazone (MBAAPS), 4[N‐(4′‐dimethoxyaminobenzylidene)amino]antipyrine semicarbazone (DABAAPS), 4[N‐(2′‐nitrobenzylidene)amino]antipyrine semicarbazone (2′‐NO₂BAAPS), and 4[N‐(3′‐nitrobenzylidene)amino]antipyrine semicarbazone (3′‐NO₂BAAPS) in non‐aqueous solvents resulted in the formation of [ThL₂X₄] (X = Cl, Br, or NCS), [ThL₂I₂]I₂, [ThL₂](ClO₄)₂ or [ThL(NO₃)₄] (L = BAAPS, MBAAPS, DABAAPS, 2‐NO₂BAAPS, or 3‐NO₂BAAPS). All of these compounds were characterized by elemental analyses, electrical conductivity, IR, and thermal methods. X‐ray powder diffraction studies of a representative complex were also undertaken. Th(IV) displays the coordination numbers 6, 8, 10, and 11 in these compounds depending on the nature of the coordinated anion and the stoichiometry.

Keywords:

• Thorium(IV)
• Semicarbazones
• Complexes
• Coordination number

Acknowledgments

One of the authors (R.K.A.) is thankful to the University Grants Commission, New Delhi, for financial assistance and Mr. Steven Sutcliffe, Chief Technician, Chemistry Department, The University of the South Pacific for his assistance in finalizing the paper.