New cyano-bridged complexes based on tetrahedral rhenium chalcocyanide clusters, Cu2+ cations, and polydentate amines

Abstract

Three new cyano bridged compounds, viz., [{Cu(en)}{Cu(NH 3 )(en)}Re 4 Se 4 (CN) 12 ]• •5H 2 O (1), [{Cu(dien)} 2 Re 4 Te 4 (CN) 12 ]•9H 2 O (2), and [{Cu(trien)} 2 Re 4 Se 4 (CN) 12 ]• •5H 2 O (3), were synthesized by the reactions of the tetrahedral rhenium chalcocyanide cluster complexes K 4 [Re 4 Q 4 (CN) 12 ] (Q = Se or Te) with copper(II) cations in aqueous solutions containing ethylenediamine (en), diethylenetriamine (dien), or triethylenetetraamine (trien), respectively. Complex 1 has a ladder tubular like polymeric structure, in which two infinite chains are linked to each other by Re-CN-Cu bridges, compound 2 has a polymeric chain structure, and compound 3 has a molecular structure. The structures of all complexes were established by X ray diffraction analysis.In recent years, the reactions of rhenium chalco cyanide cluster complexes with 3d transition metal cat ions have attracted considerable attention. 1-4 Due to the ambident character, the CN group can serve as a bridging ligand to give polynuclear compounds of different dimen sionality, viz., framework, 2,5-8 layered, 1,9-11 chain, 12-15 or molecular compounds. 14,16 The use of polydentate ligands offers additional possibilities for controlling the dimensionality of the cyano bridged compounds. 17-21 In recent years, we have carried out systematic studies of the synthesis of cyano bridged coordination polymers based on the tetrahedral rhenium cluster complexes [Re 4 Q 4 (CN) 12 ] 4-(Q = S, Se, or Te) and 3d metal com plexes with N donor ligands. The reactions of copper ammonium complexes with K 4 [Re 4 Q 4 (CN) 12 ] (Q = S, Se, or Te) were demonstrated to give chain struc tures, 15 whereas the reaction of the copper chelate complex Cu(en) 2 Cl 2 (en is ethylenediamine) with K 4 [Re 4 Te 4 (CN) 12 ] in an ammonium medium af forded a molecular compound. 21 Investigation of the Cu 2+ -dien-[Re 4 Q 4 (CN) 12 ] 4-system (dien is diethyl enetriamine) showed that both molecular and polymeric structures are produced depending on the composition of the solution. 20 In continuation of these studies, we exam ined the formation of such complexes in relation to the dentation of the N donor ligand coordinated to the Cu atom at a constant Cu : ligand ratio of 1 : 1. We used en, dien, and triethylenetetraamine (trien) as the chelating ligands. Results and DiscussionComplex 1 was prepared by the reaction of an aqueous solution

Design of Cyano‐Bridged Coordination Polymers Based on Tetrahedral Rhenium Cluster Cyanide Complexes and 3d Transition Metals

“…The interaction of K 4 [Re 4 Se 4 (CN) 12 ] with an equimolar mixture of CuCl 2 and en in aqueous ammonia solution leads to the formation of [{Cu(en)}{Cu(NH 3 )(en)}-Re 4 Se 4 (CN) 12 ]·5H 2 O (11) [27] in which the chemical form…”

“…The two isostructural compounds [{Cu 2 (dien) 3 }-Re 4 Q 4 (CN) 12 ]·nH 2 O [Q = Se (26) and Te (27)] have been synthesised following the same synthetic procedure. [33] It is very interesting to note that both these compounds have a compositions similar to that of 25, but their structures are sufficiently different.…”

“…(31), [27] Te 4 (32), [36] STe 3 (33) [32] ). trien is present in these compounds as a tetradentate ligand occupying four coordination sites.…”

“…24). [27] This compound has a chain-like structure in which the cluster anions are linked to each other through two complex {Cu(dien)} 2+ cations. An alternation of the -2Cu(dien)-cluster-2Cu(dien)fragments gives rise to a coordination-chain polymer whose structure is shown in Figure 19.…”

“…The next step of complication can be viewed in [{Cu(dien)} 2 Re 4 Te 4 (CN) 12 ] · 9H 2 O ( 24 ) 27. This compound has a chain‐like structure in which the cluster anions are linked to each other through two complex {Cu(dien)} 2+ cations.…”