Formation of Polymeric Network Arrays by Complexes of Manganese(II) or Cobalt(II) with Alkane Chain Linked Bis(amide) Ligands of Biological Relevance

Abstract

Bis(amides) of the type CH(3)CONH(CH(2))(n)()NHCOCH(3) (n = 2, 4, or 6) react with a range of manganese(II) and cobalt(II) salts to produce polymeric "framework" arrays, five of which have been studied by X-ray crystallography. Hexamethylenebis(acetamide) (HMBA) forms the compound [Co(HMBA)(3)](CoCl(4)).2EtOH in which the HMBA molecules bridge the metal centers, binding octahedrally via the oxygen atoms of the amide groups and forming cationic arrays of large rhomboidal "boxes" containing tetrahedral CoCl(4)(2-) ions. The butylenebis(acetamide) (BBA) complex [Co(BBA)(3)]Br(2) forms a sheet cationic network, but in this case, the counteranions are simple bromide ions. The ethylenebis(acetamide) (EBA) complex [Co(EBA)(2)(H(2)O)(2)]Br(2) comprises trans-octahedral [Co(O-amide)(4)(H(2)O)(2)](2+) units interlinked by the bridging action of the EBA ligands to form sheet arrays, with simple bromide counterions. From the reaction of HMBA with manganese(II) bromide two crystalline forms were obtained, [Mn(HMBA)(3)](MnBr(4)).2EtOH, with a structure similar to [Co(HMBA)(3)](CoCl(4)).2EtOH, and a solvent-free form, [Mn(HMBA)(3)](MnBr(4)), comprising a cationic sheet array. The preparations of several other transition-metal complexes with these ligands are reported together with relevant spectroscopic data.

Flexiblemeso-Bis(sulfinyl) Ligands as Building Blocks for Copper(II) Coordination Polymers: Cavity Control by Varying the Chain Length of Ligands

“…[1] Concurrent with this has been the development of multidimensional networks based primarily on the linking of metal centers by rigid bridging components. [2] Far less common has been the use of flexible bridging units in the construction of extended networks, [3] this approach is attractive because the flexibility and conformational freedom of such ligands offer the possibility of generating unique frameworks with useful properties.Herein we report the synthesis of three novel Cu II complexes with unique macrometallacyclic networks formed by using flexible meso-bis(sulfinyl) ligands (1 ± 3; Figure 1) [4] as building blocks. The underlying principles of our design are as follows: a) the ditopic coordination sites of bis(sulfinyl) may allow coordination polymers with higher dimensions; b) the pyramidal S atom is an asymmetric center to introduce acentric sites into the resulting crystals; c) the dimensions and cavity sizes of the frameworks with such ligands may be easily controlled by ligand modifications; d) bis(sulfinyl) ligands, the chemistry of which is still undeveloped, are likely to be applicable to a vast variety of metal moieties.…”

“…[1] Concurrent with this has been the development of multidimensional networks based primarily on the linking of metal centers by rigid bridging components. [2] Far less common has been the use of flexible bridging units in the construction of extended networks, [3] this approach is attractive because the flexibility and conformational freedom of such ligands offer the possibility of generating unique frameworks with useful properties.…”

Anion Control over Interpenetration and Framework Topology in Coordination Networks Based on Homoleptic Six‐Connected Scandium Nodes

“…Of the previously reported six-connected coordination polymers, only a few adopt the a-polonium-type structure. These include [Ag(pyrazine) 3 ](SbF 6 ), [6] {[Sc(O 2 CC CH) 3 ]} ¥ , [7] the doubly interpenetrated {[Mn(N,N'-butylenebisimidazole) 3 ](BF 4 ) 3 } ¥ , [8] non-interpenetrated {[Co(HMBA)] 3 (CoCl 4 )} ¥ and {[Mn(HMBA) 3 ](MnBr 4 )} ¥ (HMBA = hexamethylenebis(acetamide) [9] and the family of cyanide-bridged frameworks related to Prussian blue. [10] Of the other six-connected coordination polymers all are constructed by using more than one type of linkage between six-connected nodes [11] or, as is the case of the Cd II compound formed with hexakis(imidazolylmethyl)benzene, [12] are perhaps better described as having a NaCl-like structure as it has two distinct six-connected nodes.…”

Polymeric coordination system of [Ag2(NO3)2L]n [L=1,4-bis((cyclohexylthio)acetyl)piperazine] that exhibits supramolecular isomerism with 2D and 3D frameworks

“…While far less common has been the use of flexible ligands [8], this approach is becoming attractive recently because the flexibility and conformational freedom of such ligands offer the possibility of generating unique frameworks with useful properties. In particular, the supramolecular architecture based on the flexible ligands can be rationalised with respect to the auxiliary factors, such as anion and solvent.…”