Structural diversity in Cd(NCS)₂-3-cyanopyridine coordination compounds: synthesis, crystal structures and thermal properties

Abstract

Five new compounds with the compositions [Cd(NCS)2(3-cyanopyridine)2]n · 3-cyanopyridine (1), [Cd(NCS)2(3-cyanopyridine)2]n · 1/3 3-cyanopyridine (2), [Cd(NCS)2(3-cyanopyridine)2]n (3), {[Cd(NCS)2]2(3-cyanopyridine)3}n (4), and {[Cd(NCS)2]3(3-cyanopyridine)4}n (5) have been obtained by the reaction of Cd(NCS)2 with 3-cyanopyridine in different solvents. While large amounts of compounds 1–4 could be prepared as powders, only a few single crystals of 5 were accidently obtained. Thermoanalytical investigations have shown that 4 could also be obtained by annealing of 1 or 2 and that under slightly different conditions 5 could be obtained as part of a mixture with 4. The crystal structures of all compounds can be divided in two sets of compounds. Compounds 1, 2 and 3 consist of chains in which the Cd cations show three different coordination environments and in which the coligands are only terminally bonded. In the structures of 4 and 5 similar chains are observed, which are connected into layers via some of the 3-cyanopyridine coligands.

Synthesis, Crystal Structures and Properties of Ni(NCS)2‐3‐Cyanopyridine Coordination Compounds including a Ferromagnetic Layered Compound

“…[47][48] Some compounds consisting of transition metal thiocyanates with 3cyanopyridine are already reported. [49][50][51][52][53] For Ni only one discrete complex with the composition Ni(NCS) 2 (3-cyanopyridine) 4 is known. During our investigations, we discovered some new discrete complexes with this coligand, but also a layered compound that shows a very rare topology similar to that observed in compounds with 4-acetylpyridine and ethylisonicotinate reported recently.…”

“…In the course of our systematic work, we became interested in Ni(II) compounds with cyanopyridines as coligands, which can act as a terminal or as a bridging ligand [47–48] . Some compounds consisting of transition metal thiocyanates with 3‐cyanopyridine are already reported [49–53] . For Ni only one discrete complex with the composition Ni(NCS) 2 (3‐cyanopyridine) 4 is known.…”

Synthesis and crystal structure of structurally different cadmium selenocyanate and thiocyanate coordination compounds containing 3‐chloropyridine as ligand

“…Moreover, with Cd(NCS) 2 the structural variability is much larger and many compounds with unusual stoichiometry, unusual metal thiocyanate networks and different metal coordinations are reported in the literature. [22][23][24][25][26][27][28][29] This versatile structural behaviour is one of the reasons why we are also interested in the synthesis and crystal structure of coordination compounds based on Cd(NCS) 2 . Moreover, in several cases such compounds are isotypic to its paramagnetic analogues and therefore, can be used as structural models, e. g. for a Rietveld refinement, when no single crystals of the paramagnetic compounds are available.…”

Synthesis, Crystal Structure and Properties of a new Hydrate of Manganese Thiocyanate with the Composition Mn(NCS)2(H2O)2

“…We are interested in thiocyanate coordination compounds for several years to study, e. g. the influence of the coligand on the structural and magnetic properties of such compounds in more detail [9–12] . In the course of this project we became interested in compounds with Mn(NCS) 2 and 3‐cyanopyridine as coligand, because Mn(NCS) 2 compounds frequently behave structurally similar to Cd(NCS) 2 compounds and with Cd(NCS) 2 and 3‐cyanopyridine compounds with an unusual stoichiometry and structure are reported, that are not available with pyridine derivatives substituted in 4‐position [13] . For the synthesis, usually Mn(NCS) 2 (H 2 O) 4 prepared according to literature procedures [14] or Mn(NCS) 2 synthesized by water removal from the tetrahydrate are used as reactants and in one of these reactions crystals of two different crystalline phases were obtained, of which one contains 3‐cyanopyridine as ligand, which was not the case for the second phase.…”

“…[9][10][11][12] In the course of this project we became interested in compounds with Mn(NCS) 2 and 3-cyanopyridine as coligand, because Mn(NCS) 2 compounds frequently behave structurally similar to Cd(NCS) 2 compounds and with Cd(NCS) 2 and 3-cyanopyridine compounds with an unusual stoichiometry and structure are reported, that are not available with pyridine derivatives substituted in 4-position. [13] For the synthesis, usually Mn-(NCS) 2 (H 2 O) 4 prepared according to literature procedures [14] or Mn(NCS) 2 synthesized by water removal from the tetrahydrate are used as reactants and in one of these reactions crystals of two different crystalline phases were obtained, of which one contains 3-cyanopyridine as ligand, which was not the case for the second phase. Single-crystal structure determinations prove the formation of a compound with the composition Mn-(NCS) 2 (H 2 O) 2 , which represents a hitherto unknown hydrate of Mn(NCS) 2 .…”