Synthesis, Structures, and Properties of Transition Metal Thiocyanato Coordination Compounds with 4‐(4‐Chlorobenzyl)pyridine as Ligand

Abstract

Abstract Reactions of transition metal thiocyanates with 4‐(4‐chlorobenzyl)pyridine (Clbp) lead to the formation of compounds of composition M (NCS) 2 (4‐(4‐chlorobenzyl)pyridine) 4 ( Mn‐1 , Fe‐1/I , Fe‐1/II , Ni‐1 , and Cd‐1 ) and M (NCS) 2 (4‐(4‐chlorobenzyl)pyridine) 2 ( Mn‐2 , Ni‐2 , and Cd‐2 ). In the crystal structures of compounds M ‐1 the metal cations are octahedrally coordinated by two terminal N‐bonded thiocyanato anions and four Clbp ligands, whereas in compounds M ‐2 the metal cations are linked by μ‐1, 3‐bridging anionic ligands. IR spectroscopic investigations show that the value of the asymmetric C–N stretching vibration depends on the coordination mode of the thiocyanato ligand and the nature of the metal cations. The thermal properties were investigated by simultaneous differential thermoanalysis and thermogravimetry as well as temperature dependent X‐ray powder diffraction. On heating compound Ni‐1 looses half of the Clbp ligands and transforms into Ni‐2 . Clbp deficient intermediates were also detected on thermal decomposition of Mn‐1 and Fe‐1/I but the samples are of low crystallinity and therefore, their structures cannot be determined. Magnetic investigations reveal that Ni‐2 shows only Curie‐Weiss paramagnetism without any magnetic anomaly.