A pseudo‐cage complex of silver(I) with tripodal tetraamine having benzyl end groups, {tris[2‐(benzylamino)ethyl]amine‐κ4N}silver(I) perchlorate

The synthesis and crystal structure of {tris­[2‐(benzyl­amino)­ethyl]­amine‐κ⁴N}silver(I) perchlorate, [Ag(C₂₇H₃₆N₄)]ClO₄ or [Ag(bz₃tren)]ClO₄ {bz₃tren is tris­[2‐(benzyl­amino)­ethyl]­amine or N,N′,N′′‐tri­benzyl­tris(2‐amino­ethyl)­amine} are reported. The Ag atom is coordinated to four N atoms of the tren unit and is located 0.604 (3) Å out of the trigonal plane described by the three secondary amine N atoms, away from the bridgehead N atom. Edge‐to‐face π–π interactions between the aromatic end groups, and weak interactions between Ag and arene, allow the formation of a pseudo‐cage complex.     

Four copper(II) complexes with potentially tetradentate tripodal ligands

The four title Cu^II compounds are chloro­[(2‐furyl­methyl)­bis(2‐pyridyl­methyl)­amine‐N,N′,N′′]copper(II) perchlorate, [CuCl(C₁₇H₁₇N₃O)]ClO₄, (I), chloro{2‐[bis(2‐pyridyl­methyl)­amino]­ethano­lato‐N,N′,N′′,O}­copper(II) hemi­[tetra­chloro­copper(II)], [CuCl(C₁₄H₁₇N₃O)][CuCl₄]_1/2, (II), chloro­[(2‐morpholino­ethyl)­bis(2‐pyridyl­methyl)­amine‐N,N′,N′′,N′′′]copper(II) perchlorate, [CuCl(C₁₈H₂₄N₄O)]ClO₄, (III), and chloro­[(2‐piperidinyl­ethyl)­bis(2‐pyridyl­methyl)­amine‐N,N′,N′′,N′′′]­copper(II) hexa­fluoro­phosphate, [CuCl(C₁₉H₂₆N₄)]­PF₆, (IV). They have tripodal potentially tetradentate ligands. In (I), the O atom of the furan moiety weakly coordinates to the Cu atom at a distance of 2.750 (3) Å.     

[2‐(Imidazol‐4‐yl)ethylamine]{[2‐(imidazol‐4‐yl)ethyl][(1‐methylimidazol‐2‐yl)methyl]amine}copper(II) diperchlorate

In the title mononuclear complex, [Cu(C₅H₉N₃)(C₁₀H₁₅N₅)](ClO₄)₂, the Cu^II centre is surrounded by two N‐donor ligands, which impose a square‐pyramidal environment on the metal. The new tridentate ligand [2‐(imidazol‐4‐yl)­ethyl]­[(1‐methyl­imidazol‐2‐yl)­methyl]­amine (HISMIMA) lies in the basal plane, while the hist­amine ligand occupies the apical and one of the basal positions around the Cu^II ion.     

Bis{4‐[N,N‐bis(2‐cyano­ethyl)­amino]­pyridine‐κN1}silver(I) perchlorate,with the perchlorate anion located in the cation cavity

The title complex, bis­[3,3′‐(pyridine‐4‐imino‐κN¹)­di­propane­nitrile]silver(I) perchlorate, [Ag(CEAP)₂]ClO₄ {CEAP is 4‐[N,N‐bis(2‐cyano­ethyl)­amino]­pyridine, C₁₁H₁₂N₄}, has been prepared and characterized. The unit cell consists of two crystallographically non‐equivalent mol­ecules. Cation cavities are constructed by [Ag(CEAP)₂]⁺ cations through hydrogen bonds, and the ClO₄⁻ anions are incorporated into the cavities in μ₄‐ and μ₂‐ClO₄⁻ bridging modes through C—H⃛O hydrogen bonds.     

{2,6‐Bis­[(di­methyl­amino)­methyl]­phenyl‐N2,C1,N6}di­phenyl­tin(II) bromide monohydrate

In the title compound, [Sn(C₆H₅)₂(C₁₂H₁₉N₂)]Br·H₂O, the Sn^IV atom lies on a twofold axis and is coordinated by a C and two N atoms from the 2,6‐bis­[(di­methyl­amino)­methyl]­phenyl ligand in a tridentate fashion and by two phenyl groups. The resulting geometry is intermediate between square pyramidal and trigonal bipyramidal, with three C atoms in equatorial and the two N atoms in axial positions. The main deformation from ideal trigonal‐bipyramidal geometry is seen for the N—Sn—N angle [152.18 (7)°]. The Br^? anion and the water solvate mol­ecule are on an inversion centre and twofold axis, respectively. They form an infinite chain of Br?H—O—H?Br hydrogen bonds [Br?O 3.529 (2) Å] without contributing to the primary coordination sphere of the Sn atom.     

{2,6‐Bis­[(di­methyl­amino)­methyl]pyridine‐κ3N}(2,2‐methyl­enediphenolato‐κ2O,O′)­dioxouranium(VI) acetone solvate

In the title compound, [UO₂(C₁₃H₁₀O₂)(C₁₁H₁₉N₃)]·C₃H₆O, the U atom is in a pentagonal–bipyramidal environment, with the three N atoms of the 2,6‐bis­[(di­methyl­amino)­methyl]­pyridine ligand and the two O atoms of the dianionic 2,2′‐methyl­ene­diphenolate ligand in the equatorial plane. The geometry is compared with that of previously reported 1:2 uranyl–diphenoxide complexes.     

Bis(3,5‐di­methyl­pyrazole‐κN2)silver(I) nitrate

The two independent bis(3,5‐di­methyl­pyrazole)silver(I) cations in crystalline [Ag(C₅H₇N₂)₂]NO₃ display N—Ag—N angles of 175.51 (14) and 174.44 (13)°, and an average Ag—N distance of 2.124 (5) Å. The nitrate anion is situated between [Ag(C₅H₇N₂)₂]⁺ units and interacts via hydrogen bonds with the NH groups. The two 3,5‐di­methyl­pyrazole ligands are trans about the silver center. Only a small deviation from linearity is observed in the coordination around silver.     

Self‐assembly of a mixed‐ligand silver‐based coordination polymer

The novel title silver(I) coordination polymer, catena‐poly­[[aceto­nitrile­silver(I)]‐di‐μ‐4‐[N‐(di­phenyl­phosphino)­amino­meth­yl]­pyridine‐κ²N¹:P;κ²P:N¹‐[aceto­nitrile­silver(I)]‐μ₃‐4‐[N,N‐bis­(di­phenyl­phosphino)­amino­methyl]­pyridine‐κ³N¹:P:P′‐bis­[aceto­nitrile­silver(I)(Ag—Ag)]‐μ₃‐4‐[N,N‐bis­(di­phenyl­phosphino)­amino­methyl]­pyridine‐κ³P:P′:N¹] tetra­kis­(tetra­fluoro­borate) aceto­nitrile trisolvate], {[Ag₄(C₂H₃N)₄(C₁₈H₁₇N₂P)₂(C₃₀H₂₆N₂P₂)₂](BF₄)₄·3C₂H₃N}_n, is formed by the self‐assembly of the Ph₂P(4‐NHCH₂C₅H₄N) and (Ph₂P)₂(4‐NCH₂C₅H₄N) ligands with silver tetra­fluoro­borate. The polymer consists of alternating rings (which lie about inversion centers) bridged by the pyridyl rings of the bis‐phosphine‐substituted ligands, with anions hydrogen bonded the length of the chain. Two distinctly different metal coordination environments exist in the polymer, viz. distorted tetrahedral and trigonal geometries.     

catena‐Poly­[[(di‐2‐pyridyl­amine)­silver(I)]‐μ‐nicotinato] and catena‐poly­[[(di‐2‐pyridyl­amine)silver(I)]‐μ‐2,6‐di­hydroxy­benzoato]

In catena‐poly­[[(di‐2‐pyridyl­amine‐κ²N,N′)silver(I)]‐μ‐nico­tinato‐κ²N:O], [Ag(C₆H₄NO₂)(C₁₀H₉N₃)]_n, the Ag^I atom is tetracoordinated by two N atoms from the di‐2‐pyridyl­amine (BPA) ligand [Ag—N = 2.3785 (18) and 2.3298 (18) Å] and by one N atom and one carboxyl­ate O atom from nicotinate ligands [Ag—N = 2.2827 (15) Å and Ag—O = 2.3636 (14) Å]. Bridging by nicotinate N and O atoms generates a polymeric chain structure, which extends along [100]. The carboxyl O atom not bonded to the Ag atom takes part in an intrachain C—H⋯O hydrogen bond, further stabilizing the chain. Pairs of chains are linked by N—H⋯O hydrogen bonds to generate ribbons. There are no π–π interactions in this complex. In catena‐poly­[[(di‐2‐pyridyl­amine‐κ²N,N′)silver(I)]‐μ‐2,6‐di­hydroxy­benzoato‐κ²O¹:O²], [Ag(C₇H₅O₄)(C₁₀H₉N₃)]_n, the Ag^I atom has a distorted tetrahedral coordination, with three strong bonds to two pyridine N atoms from the BPA ligand [Ag—N = 2.286 (5) and 2.320 (5) Å] and to one carboxyl­ate O atom from the 2,6‐di­hydroxy­benzoate ligand [Ag—O = 2.222 (4) Å]; the fourth, weaker, Ag‐atom coordination is to one of the phenol O atoms [Ag⋯O = 2.703 (4) Å] of an adjacent moiety, and this interaction generates a polymeric chain along [100]. Pairs of chains are linked about inversion centers by N—H⋯O hydrogen bonds to form ribbons, within which there are π–π interactions. The ribbons are linked about inversion centers by pairs of C—H⋯O hydrogen bonds and additional π–π interactions between inversion‐related pairs of 2,6‐di­hydroxy­benzoate ligands to generate a three‐dimensional network.     

Cu2(dien)2Ag5(CN)9 containing the one‐dimensional polymeric cation [Cu(dien)Ag(CN)2]nn+ and the unusual [Ag2(CN)3]− anion (dien is diethylenetriamine)

From the 1:1 system of [Cu(dien)₂](NO₃)₂ and K[Ag(CN)₂] in water (dien is diethyl­enetri­amine, C₄H₁₃N₃), the novel compound catena‐poly­[bis­[[μ‐cyano‐1:2κ²C:N‐diethyl­enetri­amine‐2κ³N‐copper(II)silver(I)]‐μ‐cyano‐1:2′κ²C:N] di­cyano­silver(I) tri­cyanodisilver(I)], [CuAg(CN)₂(dien)]₂[Ag(CN)₂][Ag₂(CN)₃], has been isolated. The structure is formed from positively charged [–Cu(dien)–NC–Ag–CN–]_nⁿ⁺ chains and two isolated centrosymmetric [Ag(CN)₂]^? and [Ag₂(CN)₃]^? anions. In the cationic chains, the Cu atoms are linked by bridging di­cyano­argentate groups, and the deformed square‐pyramidal coordination polyhedron of the Cu^II cation is formed from a tridentate chelate‐like bonded dien ligand and two N‐bonded bridging cyano groups. One of the bridging cyano groups occupies the apical (ap) position [mean Cu—­N_eq = 2.02 (2) Å, and Cu—N_ap = 2.170 (3) Å; eq is equatorial]. Short argentophilic interactions in the range 3.16–­3.30 Å are present in the crystal structure.     

Bis(4‐aminopyridine)silver(I) nitrate and tris(2,6‐diaminopyridine)silver(I) nitrate

The bis(4‐aminopyridine)silver(I) cation in [Ag(C₅H₆N₂)₂]NO₃ has the Ag atom on a twofold axis and displays an N—Ag—N angle of 174.43 (15)° and an Ag—N distance of 2.122 (3) Å. The two ligands are planar and the angle between the two ligand planes is 79.45 (9)°. The pyridine rings are stacked in piles with an interplanar distance of 3.614 (5) Å, a distance that strongly suggests that pyridine π–π interactions have an appreciable importance with respect to the non‐bonded crystal organization. The tris(2,6‐diaminopyridine)­silver(I) cation in [Ag(C₅H₇N₃)₃]NO₃ has Ag—N distances of 2.243 (2), 2.2613 (17) and 2.4278 (18) Å, and N—Ag—N angles of 114.33 (7), 134.91 (7) and 114.33 (7)°. The Ag⁺ ion is situated 0.1531 (2) Å from the plane defined by the three pyridine N atoms.     

Linkage isomerism of organoplatinum(II) compounds coordinated by two 1,3‐di­methyl­barbiturate anions

In two linkage isomers, bis[1,3‐di­methyl‐2,4,6(1H,3H,5H)‐pyrimidine­trionato]‐C⁵,O⁴‐(ethyl­enedi­amine‐N,N′)platinum(II), [Pt(C₆H₇N₂O₃)₂(C₂H₈N₂)], (I), and bis[1,3‐di­methyl‐2,4,6(1H,3H,5H)‐py­rim­idine­tri­on­ato‐C⁵](ethyl­enediamine‐N,N′)­plati­num(II) di­hyd­rate, [Pt(C₆H₇N₂O₃)₂(C₂H₈N₂)]·2H₂O, (II), crystal­lized from the same aqueous solution containing [Pt(en)(OH)₂] and 1,3‐di­methyl­barbituric acid (Hdmbarb) in a 1:2 molar ratio, a pair of monodentate dmbarb^? anions coordinate to the Pt atom at tetrahedral C atoms for (II), while one dmbarb^? anion coordinates at the carbon and the other at a deprotonated enol oxy­gen for (I). The Pt—C distances in (I) and (II) are comparable: 2.112 (4) Å for (I), and 2.114 (4) and 2.117 (4) Å for (II).     

Polymeric structure of (ethyl­ene­diamine)silver(I) 3‐nitro­benzoate monohydrate

In the ternary title compound, catena‐poly­[[silver(I)‐μ‐ethylenedi­amine‐κ²N:N′] 3‐nitro­benzoate monohydrate], {[Ag(C₂H₈N₂)](C₇H₄NO₄)·H₂O}_n, the Ag atom is bicoordinated in a linear configuration by two different N atoms from two symmetry‐related ethyl­enedi­amine ligands, thus giving linear polymeric chains with an [–Ag—N—C—C—N–]_n backbone running parallel to the a axis. In the crystal packing, these linear chains are interconnected by N—H⃛O and O—H⃛O hydrogen bonds to form layers parallel to the ab plane.     

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.     

catena‐Poly­[[di‐μ‐benzoato‐κ4O:O′‐disilver(I)]‐μ‐N,N′‐bis(2‐fluoro­benzyl­idene)­butane‐1,4‐di­amine‐κ2N:N′]

The title complex, [Ag₂(C₇H₅O₂)₂(C₁₈H₁₈F₂N₂)]_n, is a dinuclear silver(I) compound with one inversion centre between pairs of Ag atoms and another at the mid‐point of the central C—C bond in the butane‐1,4‐diamine moiety. Each of the smallest repeat units consists of two silver(I) cations, two benzoate anions and one N,N′‐bis(2‐fluorobenzyl­idene)­butane‐1,4‐di­amine Schiff base ligand. Each Ag^I ion is three‐coordinated in a trigonal configuration by two O atoms from two benzoate anions and one N atom from a Schiff base ligand. The di‐μ‐benzoato‐disilver(I) moieties are linked by the bridging Schiff base ligand, giving zigzag polymeric chains with an [–Ag⋯Ag—N—C—C—C—C—N–]_n backbone running along the b axis.     

Retroracemization using new forms of Belokon's original ligand: ­intermediate NiII complexes of N‐({2‐[N‐(S)‐alkylprolylamino]phenyl}phenylmethylene)‐(S)‐phenylalanine (alkyl is 2‐picolyl, 3‐picolyl or ethyl)

In the title compounds, [N‐(phenyl{2‐[N‐(S)‐(2‐picolyl)­prolyl­amino]­phenyl}methyl­ene)‐(S)‐phenyl­alaninato]­nickel(II), [Ni(C₃₃H₃₀N₄O₃)], (I), [N‐(phenyl{2‐[N‐(S)‐(3‐picolyl)­prolyl­amino]­phenyl}methyl­ene)‐(S)‐phenyl­alaninato]­nickel(II) hemihydrate, [Ni(C₃₃H₃₀N₄O₃)]·0.5H₂O, (II), and [N‐({2‐[N‐(S)‐ethyl­prolyl­amino]­phenyl}phenyl­methyl­ene)‐(S)‐phenyl­ala­nin­ato]­nickel(II), [Ni(C₂₉H₂₉N₃O₃)], (III), the Ni^II centres have approximate square‐planar coordination geometries from N₃O donor sets. The picolyl N atoms in (I) and (II) are too remote from the metal centres to interact significantly, but the metal coordination geometries experience tetrahedral distortion and/or displacement of the metal centre from the N₃O plane. These are linked to conformational differences between the ligands of the symmetry‐independent complexes (Z′ = 2), which in turn are related to molecular packing. In (III), where a less sterically demanding ethyl group replaces the picolyl substituents, there are none of the distortions or displacements seen in (I) and (II).     

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.     

Tris(2,2′‐bioxazoline‐κ2N,N′)copper(II) diperchlorate and tris(2,2′‐bioxazoline‐κ2N,N′)­nickel(II) diperchlorate

In the two isomorphous title compounds, viz. tris­[2,2′‐bi(4,5‐di­hydro‐1,3‐oxazole)‐κ²N,N′]copper(II) diperchlorate, [Cu(C₆H₈N₂O₂)₃](ClO₄)₂, (I), and tris­[2,2′‐bi(4,5‐di­hydro‐1,3‐oxazole)‐κ²N,N′]­nickel(II) diperchlorate, [Ni(C₆H₈N₂O₂)₃](ClO₄)₂, (II), the M^II ions each have a distorted octahedral coordination geometry formed via six N atoms from three 2,2′‐bioxazoline ligands. For each ligand, the two five‐membered rings are nearly coplanar. It is noteworthy that the Jahn–Teller effect is stronger in (I) than in (II). The three‐dimensional supramolecular structures of (I) and (II) are formed via weak hydrogen‐bonding interactions between O atoms from per­chlorate anions and H atoms from 2,2′‐bioxazoline ligands.     

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.