Synthesis, Crystal Structures, and Thermal and Spectroscopic Properties of Thiocyanato Coordination Compounds with 3-Acetylpyridine as a Ligand

Abstract

Abstract The reaction of transition metal thiocyanates with 3-acetylpyridine (3-Acpy) leads to the formation of compounds of compositions M(NCS)2(3-Acpy)4 (M1; M = Mn, Fe, Ni) and M(NCS)2(3- Acpy)2(H2O)2 (M2; M = Mn, Fe, Ni). Thermogravimetric investigations show that in the first step some of these compounds transform into the new coordination polymers M(NCS)2(3-Acpy)2 (M3 with M = Mn, Fe and Ni), that decompose into the new compounds M(NCS)2(3-Acpy) (M4 with M = Mn and Ni) in the second step. Unfortunately, the powder patterns of compounds M3 and M4 cannot be indexed, and there are strong indications that these compounds are contaminated with a small amount of the precursor or unknown crystalline phases. IR spectroscopic investigations indicate that in compounds M3 the metal cations are linked by μ-1,3-bridging thiocyanato anions into 1D or 2D coordination polymers that are further linked by the 3-Acpy ligands in compounds M4.