NiII and ZnII complexes of the hexadentate macrocyclic ligand cis‐6,13‐di­methyl‐1,4,8,11‐tetra­aza­cyclo­tetra­decane‐6,13‐di­amine

The title pendent‐arm macrocyclic hexa­amine ligand binds stereospecifically in a hexadentate manner, and we report here its isomorphous Ni^II and Zn^II complexes (both as perchlorate salts), namely (cis‐6,13‐di­methyl‐1,4,8,11‐tetra­aza­cyclo­tetra­decane‐6,13‐di­amine‐κ⁶N)­nickel(II) di­per­chlorate, [Ni(C₁₂H₃₀N₆)]­­(ClO₄)₂, and (cis‐6,13‐di­methyl‐1,4,8,11‐tetraaza‐cyclo­tetra­decane‐6,13‐di­amine‐κ⁶N)­zinc(II) di­per­chlorate, [Zn(C₁₂H₃₀N₆)]­(ClO₄)₂. Distortion of the N—M—N valence angles from their ideal octahedral values becomes more pronounced with increasing metal‐ion size and the present results are compared with other structures of this ligand.     

5,7,7,12,14,14‐Hexamethyl‐4,11‐diaza‐1,8‐diazonia­cyclo­tetra­decane penta­cyano­nitroso­ferrate(II) dihydrate: a supramolecular compound constructed by hydrogen bonds

The title compound, (C₁₆H₃₈N₄)[Fe(CN)₅(NO)]·2H₂O, contains one [Fe(CN)₅(NO)]²⁻ dianion, two half [H₂teta]²⁺ dications (teta is 5,7,7,12,14,14‐hexa­methyl‐1,4,8,11‐tetra­aza­cyclo­tetra­decane), each lying about an independent inversion centre, and two solvent water mol­ecules, all of which are held together by hydrogen bonds to form a three‐dimensional supramolecular framework.     

A mixed‐valence manganese(III)–manganese(IV) di‐μ‐oxo complex, [(cyclam)MnO]2(ClO4)2(NO3)

The title dinuclear di‐μ‐oxo‐bis­[(1,4,8,11‐tetra­aza­cyclo­tetra­decane‐κ⁴N)­manganese(III,IV)] diperchlorate nitrate complex, [Mn₂O₂(C₁₀H₂₄N₄)₂](ClO₄)₂(NO₃) or [(cyclam)Mn­O]₂(ClO₄)₂(NO₃), was self‐assembled by the reaction of Mn²⁺ with 1,4,8,11‐tetra­aza­cyclo­tetra­decane in aqueous media. The structure of this compound consists of a centrosymmetric binuclear [(cyclam)MnO]³⁺ unit, two perchlorate anions and one nitrate anion. While the low‐temperature electron paramagnetic resonance spectra show a typical 16‐line signal for a di‐μ‐oxo Mn^III/Mn^IV dimer, the magnetic susceptibility studies also confirm a characteristic antiferromagnetic coupling between the electronic spins of the Mn^IV and Mn^III ions.     

cis‐Dinitrito(1,4,8,11‐tetra­aza­cyclo­tetra­decane‐κ4N)­chromium(III) nitrite

In the title compound, [Cr(ONO)₂(cyclam)]NO₂ (cyclam is 1,4,8,11‐tetra­aza­cyclo­tetra­decane, C₁₀H₂₄N₂), the complex cation is located on a twofold symmetry axis. The central Cr atom has a distorted octahedral coordination, involving two Cr—O bonds, with the monodentate nitrite O atoms adopting a cis configuration, and four Cr—N bonds. The mean Cr—N and Cr—O distances are 2.0895 (14) and 1.9698 (14) Å.     

Cyano­cobalt(III) complexes of penta‐ and tetra­dentate‐coordinated macrocyclic hexa­amines

The pendent‐arm macrocyclic hexa­amine trans‐6,13‐dimethyl‐1,4,8,11‐tetra­aza­cyclo­tetra­decane‐6,13‐diamine (L) may coordinate in tetra‐, penta‐ or hexa­dentate modes, depending on the metal ion and the synthetic procedure. We report here the crystal structures of two pseudo‐octa­hedral cobalt(III) complexes of L, namely sodium trans‐cyano­(trans‐6,13‐dimethyl‐1,4,8,11‐tetra­aza­cyclo­tetra­decane‐6,13‐diamine)cobalt(III) triperchlorate, Na[Co(CN)(C₁₃H₃₀N₆)](ClO₄)₃ or Na{trans‐[CoL(CN)]}(ClO₄)₃, (I), where L is coordinated as a penta­dentate ligand, and trans‐dicyano­(trans‐6,13‐dimethyl‐1,4,8,11‐tetra­aza­cyclo­tetra­decane‐6,13‐diamine)cobalt(III) trans‐dicyano­(trans‐6,13‐dimethyl‐1,4,8,11‐tetra­aza­cyclo­tetra­decane‐6,13‐diaminium)cobalt(III) tetra­perchlorate tetra­hydrate, [Co(CN)₂(C₁₄H₃₂N₆)][Co(CN)₂(C₁₄H₃₀N₆)](ClO₄)₄·4H₂O or trans‐[CoL(CN)₂]trans‐[Co(H₂L)(CN)₂](ClO₄)₄·4H₂O, (II), where the ligand binds in a tetra­dentate mode, with the remaining coordination sites being filled by C‐­bound cyano ligands. In (I), the secondary amine Co—N bond lengths lie within the range 1.944 (3)–1.969 (3) Å, while the trans influence of the cyano ligand lengthens the Co—N bond length of the coordinated primary amine [Co—N = 1.986 (3) Å]. The Co—CN bond length is 1.899 (3) Å. The complex cations in (II) are each located on centres of symmetry. The Co—N bond lengths in both cations are somewhat longer than in (I) and span a narrow range [1.972 (3)–1.982 (3) Å]. The two independent Co—CN bond lengths are similar [1.918 (4) and 1.926 (4) Å] but significantly longer than in the structure of (I), again a consequence of the trans influence of each cyano ligand.     

The monoclinic polymorph of rac‐5,7,7,12,12,14‐hexa­methyl‐1,4,8,11‐tetraazonia­cyclo­tetra­decane bis­(hexa­fluoro­germanate) tetrahydrate

X‐ray data were obtained for the monoclinic polymorph of rac‐5,7,7,12,12,14‐hexa­methyl‐1,4,8,11‐tetraazonia­cyclo­tetra­decane bis­(hexa­fluoro­germanate) tetrahydrate, (C₁₆H₄₀N₄)[GeF₆]₂·4H₂O. The tetra­aza‐macrocyclic cations lie across inversion centers in space group P2₁/c. Water mol­ecules and [GeF₆]²⁻ anions form zigzag chains, which alternate in a three‐dimensional network with the macrocyclic cations. The structure is sustained by multiple hydrogen bonds.     

trans‐Bis(cyano‐κC)(1,4,8,11‐tetraazacyclotetradecane‐κ4N)manganese(III) perchlorate,a low‐spin manganese(III) complex

The crystal structure of the low‐spin (S = 1) Mn^III complex [Mn(CN)₂(C₁₀H₂₄N₄)]ClO₄, or trans‐[Mn(CN)₂(cyclam)](ClO₄) (cyclam is the tetradentate amine ligand 1,4,8,11‐tetra­aza­cyclo­tetra­decane), is reported. The structural parameters in the Mn(cyclam) moiety are found to be insensitive to both the spin and the oxidation state of the Mn ion. The difference between high‐ and low‐spin Mn^III complexes is that a pronounced tetragonal elongation of the coordination octahedron occurs in high‐spin complexes and a slight tetragonal compression is seen in low‐spin complexes, as in the title complex.     

[(1,4,8,11‐Tetraazacyclotetradeca‐1,4,8,11‐tetrayl)tetraacetamide‐κ6N1,N4,N8,N11,O1,O8]copper(II) sulfate 4.5‐hydrate

The crystal structure of the title copper(II) complex, [Cu(C₁₈H₃₆N₈O₄)]SO₄·4.5H₂O, formed with the tetra­amide cyclam derivative 2‐(4,8,11‐triscarbamoyl­methyl‐1,4,8,11‐tetra­aza­cyclo­tetradec‐1‐yl)­acet­amide (TETAM), is described. The macrocycle lies on an inversion centre occupied by the hexacoordinated Cu atom. The four macrocyclic tertiary amines form the equatorial plane of an axially Jahn–Teller elongated octahedron. Two O atoms belonging to two diagonally opposite amide groups occupy the apical positions, giving rise to a trans‐III stereochemistry, while both the remaining pendant side arms extend outwards from the macrocyclic cavity and are engaged in hydrogen bonds with sulfate anions and co‐crystallized water mol­ecules.     

Bis­(aceto­nitrile‐κN)[(1RS,4RS,8SR,11SR)‐1,4,8,11‐tetra­aza­tetra­decane‐κ4N]copper(II) bis{tetrakis­[3,5‐bis­(tri­fluoro­methyl)­phenyl]­borate} 0.31‐hydrate

The title compound, [Cu(C₂H₃N)₂(C₁₀H₂₄N₄)](C₃₂H₁₂BF₂₄)₂·0.31H₂O, crystallizes as an ionic species with no interactions between the ions. The [Cu^II(cyclam)(MeCN)₂]²⁺ dication (cyclam is 1,4,8,11‐tetra­aza­tetra­decane), located on a 2/m symmetry site, forms as a distorted octahedral species with four Cu—N_cyclam bonds of 2.013 (2) Å and two C—N_MeCN bonds of 2.499 (4) Å. The [B{C₆H₃(CF₃)‐3,5}₄]⁻ anion, located on a twofold axis, is a distorted octahedral species. A small amount of water is present, occupying sites between columns of ions.     

A dinuclear uranium(IV) complex of the chelating ligand 1,2,3,4‐tetra­methyl‐5‐(2‐pyridyl)­cyclo­penta­diene

The ligand 1,2,3,4‐tetra­methyl‐5‐(2‐pyridyl)­cyclo­penta­diene (cp*py) forms a dinuclear complex with U^IV, i.e. di‐μ‐oxo‐bis­{chloro­(diethyl ether‐κO)[(η⁵,κN)‐1,2,3,4‐tetra­methyl‐5‐(2‐pyridyl)­cyclo­penta­dienyl]uranium(IV)}, [U₂Cl₂O₂(C₁₄H₁₆N)₂(C₄H₁₀O)₂], in which cp*py acts as a chelating ligand, being bound to the metal atom by the cyclo­penta­dienyl unit and also by the N atom of the pyridyl ring.     

trans‐Dioxocyclam (1,4,8,11‐tetraazacyclotetradecane‐2,9‐dione) dihydrate and its NiII complex

The crystal structures are reported of trans‐dioxocyclam dihydrate, C₁₀H₂₀N₄O₂·2H₂O, a structural isomer of the well known cis‐dioxocyclam, and of its novel Ni complex, (1,4,8,11‐tetra­aza­cyclo­tetra­decane‐2,9‐dionato‐κ⁴N)­nickel(II) dihydrate, [Ni(C₁₀H₁₈N₄O₂)]·2H₂O, the first example of a trans­ition metal complex of this ligand. Both mol­ecules lie on crystallographic centres of inversion. The free ligand has two of its N atoms turned outwards from the ring and hydrogen bonded to water mol­ecules. A major conformational change takes place in the complex in which the ligand binds in a trans tetradentate fashion, as suggested by the electronic spectrum. The nickel(II) ion is low spin, although the electronic spectrum of the complex in water indicates an equilibrium mixture of low‐spin and high‐spin species. The irreversible electrochemical oxidation of [NiL¹] (L¹ is deprotonated trans‐dioxocyclam, C₁₀H₁₈N₄O₂) in water occurs at a potential of 0.964 V [versus SHE (standard hydrogen electrode)], which is very similar to that for the Ni–cis‐dioxocyclam complex.     

Copper(I) and copper(II) complexes of an ethylene cross‐bridged cyclam

The preparation and crystal structures of (4,11‐di­benzyl‐1,4,8,11‐tetra­aza­bi­cyclo­[6.6.2]­hexa­decane‐κ⁴N)copper(I) hexa‐fluorophosphate, [Cu(C₂₆H₃₈N₄)]PF₆, and acetonitrile(4,11‐dibenzyl‐1,4,8,11‐tetraazabicyclo[6.6.2]hexadecane‐κ⁴N)‐copper(II) bis(hexafluorophosphate), [Cu(C₂H₃N)(C₂₆H₃₈‐N₄)](PF₆)₂, are described. The Cu^I ion is tetracoordinated in a very distorted tetrahedron, while the Cu^II analogue is pentacoordinated in a square pyramid.     

Di­spiro­[fluorene‐9,5′‐[1,2,3,4]­tetra­thia­ne‐6′,9′′‐fluorene]

The tetra­thia­ne ring of the title compound, C₂₆H₁₆S₄, has a chair conformation and the mol­ecule has approximate C₂ symmetry. Each of the two fluorene ring systems is virtually planar, with the ring planes intersecting at an angle of 67.58 (5)°. This novel compound has been formed as a side product from the treatment of 9H‐fluorene‐9‐thione with methyl N‐[(benzyl­idene)­phenyl]­glycinate in the presence of LiBr and 1,6‐di­aza­bi­cyclo­[5.4.0]­un­decane.     

(μ‐C‐meso‐5,5,7,12,12,14‐Hexa­methyl‐1,4,8,11‐tetra­aza­cyclo­tetra­decane‐N‐acetato‐1κ5N,N′,N′′,N′′′,O:2κO′)­tetra­chloro‐1κCl,2κ3Cl‐cobalt(III)­zinc(II)

The crystal structure of the title compound, [CoCl(C₁₈H₃₇N₄O₂){ZnCl₃}], has been determined by X‐ray diffraction.C‐meso‐5,5,7,12,12,14‐Hexa­methyl‐1,4,8,11‐tetra­aza­cyclotetradecane‐N‐acetate acts as a bridging ligand to coodinate with Co^III and Zn^II ions. The Co^III ion is six‐coordinate in a nearly octahedral environment provided by one Cl atom, four N atoms of the bridging ligand, and one O atom. The Zn^II ion is four‐coordinate in a distorted tetrahedral environment completed by three Cl atoms and an O atom of the bridging ligand.     

The NiII,HgII and CuII complexes of 12‐membered‐ring mixed‐donor macrocycles

The structures of di­aqua(1,7‐dioxa‐4‐thia‐10‐aza­cyclo­do­decane)­nickel dinitrate, [Ni(C₈H₁₇NO₂S)(H₂O)₂](NO₃)₂, (I), bis­(nitrato‐O,O′)(1,4,7‐trioxa‐10‐aza­cyclo­do­decane)­mercury, [Hg(NO₃)₂(C₈H₁₇NO₃)], (II), and aqua­(nitrato‐O)(1‐oxa‐4,7,10‐tri­aza­cyclo­do­decane)copper nitrate, [Cu(NO₃)(C₈H₁₉N₃O)(H₂O)]NO₃, (III), reveal each macrocycle binding in a tetradentate manner. The conformations of the ligands in (I) and (III) are the same and distinct from that identified for (II). These differences are in agreement with molecular‐mechanics predictions of ligand conformation as a function of metal‐ion size.     

A novel hydrogen‐bonded microporous framework constructed from two different metal complexes

A hydrogen‐bonded coordination supramol­ecule, (meso‐5,7,­7,­12,14,14‐hexa­methyl‐1,4,8,11‐tetra­aza­cyclo­tetra­decane‐κ⁴N)­nickel(II) [N,N‐o‐phenylenebis­(oxamato)­‐κ⁴O,N,N′,O′]nickelate(II) dihydrate, [Ni(C₁₆H₃₆N₄)][Ni(C₁₀H₄N₂O₆)]·2H₂O or [Ni(meso‐cth)]­[Ni(opba)]·2H₂O, has been prepared and characterized by X‐ray crystallographic analysis. The two complex ions, i.e. [Ni(meso‐cth)]²⁺ and [Ni(opba)]^2?, are hydrogen bonded to each other, resulting in two‐dimensional neutral supramolecular sheets. The sheets stack along the a direction to produce a three‐dimensional architecture with one‐dimensional channels in which hydrogen‐bonded chains of water mol­ecules are included.     

4,10‐Dinitro‐2,6,8,12‐tetraoxa‐4,10‐diazaisowurtzitane (TEX): a nitramine with an exceptionally high density

The title compound (systematic name: 4,10‐di­nitro‐2,6,8,12‐tetraoxa‐4,10‐di­aza­tetra­cyclo­[5.5.0.0^3,11.0^5,9]­do­decane), C₆H₆N₄O₈, exhibits the highest density among known N‐nitramines, due to its close‐packed crystal structure. It may be regarded as consisting of a distorted hexagonal close‐packed lattice formed by the isowurtzitane cages, with the nitro groups occupying the free space between the cages.     

Λ‐{1,4,7,10‐Tetrakis­[(S)‐2‐hydroxy­propyl‐κO]‐1,4,7,10‐tetra­aza­cyclo­do­decane‐κ4N}cadmium(II) bis(2,4,6‐tri­nitro­phenolate) aceto­nitrile solvate

Crystallization of [Cd(S‐thpc12)](ClO₄)₂·H₂O {S‐thpc12 is 1,4,7,10‐tetrakis­[(S)‐2‐hydroxy­propyl]‐1,4,7,10‐tetra­aza­cyclo­do­decane} in the presence of two equivalents of sodium picrate monohydrate (sodium 2,4,6‐tri­nitro­phenolate monohydrate) diastereoselectively produces a neutral receptor complex, viz. the title compound, Λ‐[Cd(C₂₀H₄₄N₄O₄)](C₆H₂N₃O₇)₂·CH₃CN. In this complex, two picrate anions hydrogen bond, via their phenolate moieties, to the pendant hydroxyl groups of the receptor which, together with the four N atoms, themselves bond to Cd^II in an approximately cubic arrangement. One picrate anion hydrogen bonds to all four hydroxyl groups, one of which also acts as the sole hydrogen‐bond donor to the second picrate anion.     

cis‐Dioxocyclam

Molecules of 1,4,8,11‐tetra­aza­cyclo­tetra­decane‐5,7‐dione, or cis‐dioxocyclam, C₁₀H₂₀N₄O₂, lie across mirror planes in space group Cmca; the crystal structure reveals interleaved columns of cis‐dioxocyclam mol­ecules along the 2₁ screw axis parallel to the crystallographic b axis. The columns are interconnected in a chain‐like arrangement by an amido hydrogen‐bonding network (N?O = 2.816 Å) and an amino hydrogen‐bonding network (N?N = 3.193 Å). The intracolumn spacing is 9.02 Å.     

(Borohydrido)(18‐crown‐6)potassium and (borohydrido)(dibenzo‐18‐crown‐6)(tetra­hydro­furan)potassium

In the two compounds (borohydrido)(1,4,7,10,13,16‐hexa­oxacyclo­octa­decane‐κ⁶O)potassium, [K(BH₄)(C₁₂H₂₄O₆)], (I), and (borohydrido)(1,4,7,10,13,16‐hexa­oxa‐2,3:11,12‐di­benzo­cyclo­octa­deca‐2,11‐diene‐κ⁶O)(tetra­hydro­furan)­potassium, [K(BH₄)(C₄H₈O)(C₂₀H₂₄O₆)], (II), the K atom is bound to the six O atoms of the crown ether and to a tridentate borohydride group, with further coordination to a tetra­hydro­furan mol­ecule in (II). The alkali metal ion environment is thus distorted hexa­gonal–pyramidal in (I) and bipyramidal in (II).