Heterodinukleare Cobalt(II)‐, Nickel(II)‐, Kupfer(II)‐, Zink(II)und Palladium(II)‐Komplexe mit einem makrocyclischen Liganden vom Schiff‐Basen‐Typ: Synthesen und Strukturen

Complexes with Macrocyclic Ligands. IV. Heterodinuclear Cobalt(II), Nickel(II), Copper(II), Zinc(II) and Palladium(II) Complexes with a Macrocyclic Ligand of Schiff‐Base Type: Syntheses and Structures The synthesis and properties of nickel(II), copper(II), and palladium(II) complexes, [ML^Ph] ( 3 ; L^Ph = N,N′‐phenylene‐bis(3‐formyl‐5‐tert.‐butyl‐salicylaldimine)), are described. These neutral mononuclear complexes react with metal(II) perchlorate and 1,3‐propylenediamine to form heterodinuclear, macrocyclic, cationic complexes of the type [MM′(L^Ph,3)]²⁺ ( 4 ; M = Ni, Cu, Pd; M′ = Co, Cu, Zn). The structures of the five new compounds [NiCo(L^Ph,3)](ClO₄)₂, [NiCu(L^Ph,3)](ClO₄)₂, [CuCu(L^Ph,3)](ClO₄)₂, [CuZn(L^Ph,3)](ClO₄)₂, and [PdCu(L^Ph,3)](ClO₄)₂ were determined by X‐ray diffraction.     

Nickel(II)‐Komplexe von Oxalamidinen und Oxalamidinaten mit zusätzlichen R2P‐Donorgruppen

Complexes of Nickel(II) with Oxalic Amidines and Oxalic Amidinates with Additonal R₂P‐Donor Groups Oxalamidines R¹N=C(NHR²)‐C(=NHR²)=NR¹, which bear additional donor atoms at two of the four N substituents ( H₂A : R¹ = mesityl, R² = ‐(CH₂)₃‐PPh_2; H₂B : R¹ = tolyl, R² = ‐(CH₂)₃‐PMe₂) form binuclear complexes with Nickel(II) in which very different coordination modes are realized. In the complex [ (A) Ni₂Br₂] (1) the two nickel atoms at each side of the bridge are in a square‐planar environment, coordinated by the two N donor atoms of the oxalic amidinate framework, a bromide and a Ph₂P group. An analogous coordination has the organometallic compound [ (A) Ni₂Me₂] (2) . In contrast, the two nickel atoms in the compound {[( B )][Ni(acac)]₂} (5) differ in their coordinative environment. At one side of the oxalic amidinate bridging ligand a (acac)Ni fragment is coordinated by the two N donor atoms resulting in a square‐planar environment. At the opposite side the (acac)Ni fragment is coordinated at the both N donor ligands of the bridging ligand as well as at the two PMe₂ groups of the side chains resulting in an octahedral coordination for this nickel atom.     

Polyol‐Metall‐Komplexe.47 Kristalline D‐Mannose‐Kupfer(II)‐Komplexe aus Fehlingscher Lösung

Polyol Metal Complexes.47¹⁾ Crystalline D ‐Mannose‐Copper Complexes from Fehling Solutions Blue, unstable crystals of K₃[Cu₅(β‐D ‐Manp)₄H_—13] · α‐D ‐Manp · 16.5 H₂O ( 1 ), which contain a pentanuclear cupric complex of the reducing sugar D ‐mannose in its β‐pyranose form (β‐D ‐Manp), have been obtained from ice‐cold aqueous alkaline solutions. The homoleptic pentacuprate contains bridging mannopyranose ligands, which are charged 4— and 2.5—. Addition of ethylenediamine (en) to such Fehling solutions yields N, N′‐Bis(β‐D ‐mannopyranosyl)‐ethylenediamine (L) as a condensation product of the diamine and mannopyranose. Crystals of [(en)₂Cu₇(β‐D ‐Manp1, 2, 3, 4H_—4)₂(L2, 3, 4H_—3)₂] · 26.6 H₂O ( 2 ) could be isolated. The heptanuclear cupric complex is a structural derivative of the homoleptic mannose complex.     

Dinukleare Kupfer(II)‐Komplexe mit chiralen makrocyclischen Liganden vom Schiff‐Basen‐Typ: Synthesen und Strukturen

Complexes with Macrocyclic Ligands. V Dinuclear Copper(II) Complexes with Chiral Macrocyclic Ligands of Schiff‐Base Type: Syntheses and Structures The synthesis and properties of four chiral, dinuclear, macrocyclic, cationic copper(II) complexes, [Cu₂(L^m,n)]²⁺ ( 1 – 4 ), are described. The two symmetrical compounds [Cu₂(L^2,2)][ClO₄]₂ ( 1 and 2 ) were synthesized in a one‐step reaction from 2,6‐diformyl‐4‐tert.‐butylphenol, copper(II)‐perchlorate and the chiral diamine (1S,2S)‐1,2‐diphenylethylenediamine (synthesis of 1 ) and (1R,2R)‐1,2‐diaminocyclohexane (synthesis of 2 ), respectively. For the synthesis of the two unsymmetrical compounds [Cu₂(L^Ph,n)][ClO₄]₂ ( 3 and 4 ) the mononuclear, neutral copper(II) complex [CuL^Ph] ( 5 ) [synthesized from 2,6‐diformyl‐4‐tert.‐butylphenol, copper(II)‐acetate and 1,2‐phenylenediamine] was reacted with (1R,2R)‐1,2‐diaminocyclohexane (synthesis of 3 ) and (S)‐1,1′‐binaphthyl‐2,2′‐diamine (synthesis of 4 ), respectively. The structures of the two unsymmetrical copper(II) compounds ( 3 and 4 ) were determined by X‐ray diffraction.     

Binukleare Nickel(II)‐Komplexe mit Oxalamidinaten als Brückenliganden: Synthese und Strukturen von Verbindungen mit planarer,tetraedrischer, tetragonal‐pyramidaler und oktaedrischer Koordination

Binuclear Nickel(II) Complexes with Oxalamidinates as Bridging Ligands: Synthesis and Struktures of Compounds with Planar, Tetrahedral, Tetragonal‐pyramidal, and Octahedral Coordination Oxalamidines R¹–NH–C(=NR²–C(=NR²)–NH–R¹ react selectively with Ni(acac)₂ under formation of the planar complexes [(acac)Ni(oxalamidinate)Ni(acac)]. Two crystal structures of the binuclear complexes with R = R′ = Ph ( 1 ) or p‐tolyl ( 2 ) show that the bridging oxalamidinates bind as bidendate ligands at each Nickel(II) atom. In contrast, the more sterically demanding fragment (Ph₃P)NiBr can only coordinate at sterically less demanding oxalamidinates to form complexes of the type [(Ph₃P)NiBr]₂(oxalamidinate) with tetrahedral coordination of Ni^II found by X‐ray analyses. Oxalamidines containing additional donor atoms in the side arms react very different, but in each case under formation of binuclear complexes, such as [(acac)₂Ni]₂( H₂E ) ( 8 ) (with R¹: –(CH₂)₃PPh₂, R²: p‐tolyl) in which the oxalamidine acts as bidentate neutral P,N‐ligand and the Ni^II atom has an octahedral environment. H₂F (with R¹: –(CH₂)₃PPh₂, R²: Mesityl), however, yields the planar complex [(acac)Ni]₂( F ) ( 9 ) with dianionic oxalamidinate under elimination of acetylacetone. There is no coordination of the donor groups of the side arms in the solid state of complex 9 , in contrast to the analogous binuclear complex [(acac)Ni]₂( H ) 10 (R¹: –CH₂–CH₂‐2‐pyridyl, R²: Mesityl). In this complex a distorted tetragonal‐pyramidal coordination of Ni^II is achieved. 2 reacts with an excess of LiCH₃ under elimination of the oxalamidinate to form the cluster compound Li₄(THF)₄Ni₂Me₈ in very good yields, while 9 yields the THF poorer cluster Li₂(THF)₂Li₂Ni₂Me₈ under similar conditions.     

Magnetic Exchange Interactions in Dinuclear Copper(II) and Nickel(II) Complexes with μ‐Oxalato Bridges. The Structure of μ‐Oxalato(O,O′, O″, O‴)‐bis{[1, 8‐di(2‐pyridyl)‐3, 6‐dithiaoctane‐N,N′, S,S′]nickel(II)} Dinitrate Dihydrate

A copper(II) and two nickel(II) dinuclear oxalato‐bridged compounds of formulae [{Cu(bpdto)}₂(μ‐ox)](ClO₄)₂ ( 1 ), [{Ni(bpdto)]₂(μ‐ox)](ClO₄)₂( 2 ), and [{Ni(bpdto)}₂(μ‐ox)](NO₃)₂·2H₂O ( 3 ), where bpdto = 1, 8‐bis(2‐pyridyl)‐3, 6‐dithiaoctane and ox = oxalate = C₂O₄^2— anion, have been synthesized and characterized. The crystal structure of 3 was determined by single‐crystal X‐ray analysis. It is a dinuclear complex with i symmetry in which the oxalate ligand is coordinated in bis(didentate) fashion to the inversion centre‐related nickel atoms. The distorted octahedral environment of each nickel atom is completed by two sulphur atoms in the equatorial plane and by two pyridyl nitrogen atoms in axial positions. Magnetic susceptibility measurements over the range 5 — 299K, show antiferromagnetic interactions that are weak in 1 (J = —12.8 cm^—1) and strong in 2 and 3 (J = —37.8 and —40.9 cm^—1, respectively), which in the case of 3 is in keeping with the observed structural parameters.     

3‐(Arylhydrazono)pentane‐2, 4‐diones and their Complexes with Copper(II) and Nickel(II) — Synthesis and Crystal Structures

A series of new 3‐(arylhydrazono)pentane‐2, 4‐diones ( 1 ‐ 6 ) synthesized from pentane‐2, 4‐dione and diazonium salts of respective anilines using the procedure of Japp‐Klingemann are described. Complexes with Cu^II and Ni^II salts are prepared ( 7 ‐ 10 , respectively). Spectroscopic properties of these compounds have been studied and X‐ray crystal structures of selected hydrazones ( 3 , 4 , 6 ) and of the hydrazone complexes ( 7 ‐ 10 ) are reported. The structures of the uncomplexed hydrazones feature an intramolecular N‐H···O interaction to yield a six‐membered H‐bond ring reflecting preference of the hydrazone tautomeric structure. All the complexes are mononuclear 2:1 (L:M) structures of six‐membered chelate type involving N₂O₂ binding sites that are quadratic arranged but differ in the entire coordination environment dependent on the metal and the ligand substitution including distorted octahedral and quadratic pyramidal coordination geometries in the Cu^II complexes 7 and 8 or nearly regular square planar coordination geometry in the Ni^II complexes 9 and 10 , respectively. In the crystal packings, strong and weak H‐bond interactions cause supramolecular network structures.     

Nickel(I)‐Komplexe mit 1,1′‐Bis(phosphino)ferrocenen als Liganden

Nickel(I) Complexes with 1,1′‐Bis(phosphino)ferrocenes as Ligands The thermically stable monomeric Nickel(I) complexes [(d^tbpf)Ni(acac)] ( 1 ) and [(dⁱppf)NiCl] ( 2 ) were synthesized and characterized by elemental analyses, EPR spectroscopy, and by X‐ray crystal structure analyses of single crystals (d^tbpf: 1,1′‐bis(di‐tertbutylphosphino)ferrocene; dⁱppf: 1,1′‐bis(diisopropylphosphino)ferrocene). 1 is formed by reduction of Ni(acac)₂ with triethylaluminium in the presence of d^tbpf, together with the nickel(0) complex [(d^tbpf)Ni(C₂H₄)]. 1 contains a Ni^I atom surrounded of two O‐ and two P donor atoms in a distorted tetrahedral coordination. 2 was obtained by reduction of [(dⁱppf)NiCl₂] with NaBH₄. In 2 the nickel(I) atom adopts trigonal planar coordination.     

Synthese und Charakterisierung von Cobalt(II)‐ und Kupfer(I)‐Komplexen mit Guanidin‐Pyridin‐Hybridliganden

Syntheses and Structures of Cobalt(II) and Copper(I) Complexes with Guanidine‐Pyridine Hybridligands The guanidine‐pyridine hybridligands N‐(1,3‐dimethylimidazolidin‐2‐ylidene)‐2‐(pyridine‐2‐yl)ethanamine (DMEGepy, L1 ) and 1,1,3,3‐tetramethyl‐2‐(2‐(pyridine‐2‐yl)ethyl)guanidine (TMGepy, L2 ) have been synthesized and characterized. The reaction of DMEGepy with CoCl₂ and TMGepy with CuI lead to the mononuclear complexes {N‐(1,3‐dimethylimidazolidin‐2‐ylidene)‐2‐(pyridine‐2‐yl)ethanamine}cobalt(II) dichloride ( 1 ) and {1,1,3,3‐tetramethyl‐2‐(2‐(pyridine‐2‐yl)ethyl)guanidine}copper(I) iodide ( 2 ). By the characterization of these complexes we are able to compare the complexation chemistry of the hybridguanidine and bisguanidine ligands with regard to the various N donor functions systematically.     

Synthese und Kristallstrukturen der Phosphanimin-Komplexe [Cu(μ-HNPEt3)]4(O3S–CF3)4 und [Pt2Me6(μ-I)2(μ-HNPMe3)]

Synthesis and Crystal Structures of the Phosphaneimine Complexes [Cu(μ-HNPEt₃)]₄(O₃S–CF₃)₄ and [Pt₂Me₆(μ-I)₂(μ-HNPMe₃)] The title compounds have been prepared by the reaction of copper(I)triflate with [NiBr(NPEt₃)]₄ in CH₂Cl₂ suspension in the presence of water, and by the reaction of [PtMe₃I]₄ with Me₃SiNPMe₃ in boiling toluene in the presence of cesium fluoride, respectively. According to the crystal structure determinations the cation of the copper complex forms tetrameric units [Cu(HNPEt₃)]₄⁴⁺ with S₄ symmetry with Cu–N bond lengths of 191.6 and 192.1 pm. In the platinum complex the platinum atoms are linked by two μ-I bridging atoms as well as by the μ-N atom of the HNPMe₃ ligand with Pt–N bond lengths of 228.1 and 229.5 pm.     

Metallkomplexe mit N2O2S2‐Koordinationssphäre. Synthese und Charakterisierung der Cobalt(II)‐, Nickel(II)‐ und Kupfer(II)‐Komplexe eines 15‐ und eines 16‐gliedrigen N,N′‐bis(2‐hydroxyethyl)‐funktionalisierten makrocyclischen Liganden

Metal Complexes with N₂O₂S₂ Donor Set. Synthesis and Characterization of the Cobalt(II), Nickel(II), and Copper(II) Complexes of a 15‐ and a 16‐Membered Bis(2‐hydroxyethyl) Pendant Macrocyclic Ligand The macrocyclic ligands 6, 10‐bis(2‐hydroxyethyl)‐7, 8, 9, 11, 17, 18‐hexahydro‐dibenzo‐[e, n][1, 4, 8, 12]‐dithiadiaza‐cyclopentadecine ( 1 ) (L¹) and 5, 13‐bis(2‐hydroxyethyl)‐7, 8, 9, 10, 16, 17, 18, 19, 20‐nonahydro‐dibenzo‐[g, o][1, 9, 5, 13]‐dithiadiaza‐cyclohexadecine (L⁴) have been prepared. They form the stable complexes [CoL¹(‐H)CoL¹](ClO₄)₃ ( 2 ), [NiL¹](ClO₄)₂·MeOH ( 3 ), Λ‐[CuL¹](ClO₄)₂·MeOH ( 4a ) and rac‐[CuL¹](ClO₄)₂·MeOH ( 4b ), [NiL⁴](ClO₄)₂ ( 5 ), and [CuL⁴](ClO₄)₂ ( 6 ). The compounds 1 to 6 have been characterized by standard methods and single‐crystal X‐ray diffraction. In the complexes 2 to 6 the metal atoms are octahedrally coordinated by the N₂O₂S₂ donor set of the ligands. L¹ and L⁴ are folded herein along the N···M···S‐ and the N···M···N′‐axes, respectively. This results at the metal atom in a all‐cis‐configuration for the complexes of L¹ and a trans‐N₂‐cis‐O₂‐cis‐S₂‐configuration for the complexes of L⁴. The cobalt(II) complex 2 is a dimer, bridged by a rather short hydrogen bridge of 2.402(12)Å length. The copper(II) complexes of L¹ and L⁴ differ with respect to the Jahn‐Teller‐distortion.     

Heteronukleare Komplexverbindungen mit Metall—Metall-Bindungen. VIII. Neue heterodinukleare Komplexe mit Bindungen zwischen Kupfer(I) und Mangan(–I), Eisen(–I) oder Cobalt(–I)

Heteronuclear Coordination Compounds with Metal—Metal Bonds. VIII. New Heterodinuclear Complexes with Bonds between Copper(I) and Manganese(?I), Iron(?I), or Cobalt(?I) [(en)Cu? Mn(CO)₅] ( 1a ), [(dien)Cu? Mn(CO)₅] ( 1b ), [(en)Cu? Fe(CO)₃(NO)] ( 2a ), [(dien)Cu? Fe(CO)₃(NO)] ( 2b ), [(en)Cu? Co(CO)₄] ( 3a ), and [(dien)Cu? Co(CO)₄] ( 3b ) are new heterobinuclear metal—metal bonded complexes. The geometry of the [Mn(CO)₅]^?, [Fe(CO)₃(NO)]^?, and [Co(CO)₄]^? ions is distorted only to a less extend in accord with a heteropolar bond to copper.     

Mononukleare Kupfer(II)‐Komplexe von dioxaalkylenund alkylenverbrückten Bis‐isoharnstoffen

Mononuclear Copper(II) Complexes of Dioxaalkylene and Alkylene Bridged Bis‐isoureas By reaction of N‐benzoylthiocarbamic‐O,S‐diethylester with primary diamines (oxa)alkylene bridged isoureas 1 have been prepared. They yield with Cu^II neutral chelates 2 with tetradentate ligand coordination. The structures of the ligand 1 a and of the related Cu^II complex 2 a have been determined by X‐ray crystal structure analysis. They show an enamine tautomer in the ligand and a slightly tetrahedrally distorted coordination with an (oxa)alkylene bridge between the trans arranged N ligator atoms in the complex.     

Structural Study of Nickel(II), Copper(II), and Palladium(II) Complexes of 2‐Pyridineformamide 3‐Hexamethyleneiminylthiosemicarbazone

Reduction of 2‐cyanopyridine by sodium in the presence of 3‐hexamethyleneiminylthiosemicarbazide produces 2‐pyridineformamide 3‐hexamethyleneiminylthiosemicarbazone, HAmhexim. Complexes with nickel(II), copper(II) and palladium(II) have been prepared and the following complexes structurally characterized: [Ni(Amhexim)OAc], [{Cu(Amhexim)}₂C₄H₄O₄]·2DMSO·H₂O, [Cu(HAmhexim)Cl₂] and [Pd(Amhexim)Cl]. Coordination is via the pyridyl nitrogen, imine nitrogen and thiolato or thione sulfur atom when coordinating as the anionic or neutral ligand, respectively. [{Cu(Amhexim)}₂C₄H₄O₄] is a binuclear complex with the two copper(II) ions bridged by the succinato group in [Cu‐(HAmhexim)Cl₂] the Cu atom is 5‐coordinate and close to a square pyramid structure and in [Ni(Amhexim)OAc] and [Pd(Amhexim)Cl] the metal atoms are planar, 4‐coordinate.     

Darstellung,Kristallstruktur und Eigenschaften des Kupfer(II)‐Indium(III)‐Orthophosphats Cu3In2[PO4]4

Contributions on Crystal Chemistry and Thermal Behaviour of Anhydrous Phosphates. XXIV. Preparation, Crystal Structure, and Properties of Copper(II) Indium(III) Orthophosphate Cu₃In₂[PO₄]₄ Crystals of Cu₃In₂[PO₄]₄ were grown by chemical vapour transport (temperature gradient 1273 K → 1173 K) using chlorine as transport agent. The mixed metal phosphate forms a new structure type (P2₁/c, Z = 2, a = 8.9067(6), b = 8.8271(5), c = 7.8815(5) Å, β = 108.393(5)°, 13 atoms in asymmetric unit, 2549 unique reflections with F_o > 4σ, 116 variables, R(F²) = 0.065). The crystal structure shows a hexagonal closest packing of [PO₄]^3– tetrahedra. Close‐packed layers parallel (1 0 –1) are stacked according to the sequence A, B, A′, B′, A. The octahedral interstices in this packing are completely occupied by two In³⁺, one (Cu1)²⁺ and a “dumb bell” (Cu2)₂⁴⁺. In the latter case four of the six phosphate groups that belong to this octahedral void act as bi‐dentate ligands, thus forming dimers [(Cu2)₂O₁₀] with d_Cu–Cu = 3.032 Å. Cu₃In₂[PO₄]₄ is paramagnetic (μ_eff = 1.89 μ_B, θ_P = –16.9 K). The infrared and UV/Vis reflectance spectra are reported. The observed d‐electron levels of the Cu²⁺ cations agree well with those obtained from angular overlap calculations.     

Synthesis,Structure, and Spectroscopic Properties of Copper(II) and Nickel(II) Complexes Containing the 1, 4, 7‐Triisopropyl‐1, 4, 7‐triazacyclononane Ligand

Three new complexes [CuL(N₃)₂] ( 1 ), [CuL(SCN)₂] ( 2 ), and [NiL(SCN)₂] ( 3 ) (L = 1, 4, 7‐triisopropyl‐1, 4, 7‐triazacyclononane, [—NR—C₂H₄—NR—C₂H₄—NR—C₂H₄—], R = i‐Pr) have been synthesized and structurally characterized. The three complexes all crystallize in the monoclinic space group P2₁/n, with the unit cell parameters a = 9.100(5), b = 19.492(11), c = 11.646(6)Å, β = 94.526(9)° for 1 , a = 10.148(3), b = 13.611(5), c = 15.777(6)Å, β = 95.412(6)° for 2 and a = 9.270(7), b = 16.629(14), c = 14.886(12)Å, β = 101.217(15)° for 3 . The central copper(II) and nickel(II) ions are coordinated to five nitrogen atoms, three of which from the L and two from N₃^— or SCN^—, forming a slightly distorted square pyramidal geometry. Moreover, elemental analysis, IR, UV‐vis and ESR spectra of complexes 1 ‐ 3 were also determined.     

Phosphaniminato‐ und Phosphanimin‐Komplexe von Nickel(II). Die Kristallstrukturen von [Ni(O3SCF3)(NPMe3)]4, [Ni4Br5{NP(NMe2)3}3], [NiBr2{HNP(NMe2)3}2] und [Ni(PMePh2)4]

Phosphoraneiminato‐ and Phosphaneimine Complexes of Nickel(II). Crystal Structures of [Ni(O₃SCF₃)(NPMe₃)]₄, [Ni₄Br₅{NP(NMe₂)₃}₃], [NiBr₂{HNP(NMe₂)₃}₂], and [Ni(PMePh₂)₄] Black‐violet single crystals of [Ni(O₃SCF₃)(NPMe₃)]₄ ( 1 ) have been prepared from [NiBr(NPMe₃)]₄ and copper(I)triflate by metathesis reaction. The nickel atoms are associated via μ₃‐N bridges of the (NPMe₃^–) groups to form a heterocubane. The triflate ions are bonded to the Ni atoms in a chelate fashion. Blue single crystals of [Ni₄Br₅{NP(NMe₂)₃}₃] ( 2 ) are obtained by the reaction of NiBr₂ with Me₃SiNP(NMe₂)₃ in boiling toluene in the presence of sodium fluoride. The Ni atoms in 2 are associated with three μ₃‐bridged nitrogen atoms of the (NP(NMe₂)₃^–) groups as well as by a μ₃‐Br atom to give a distorted heterocubane. Deep blue single crystals of the phosphaneimine complex [NiBr₂{HNP(NMe₂)₃}₂] ( 3 ) are formed from Me₃SiNP(NMe₂)₃ and NiBr₂ in boiling dichloromethane. In 3 the Ni atom is tetrahedrally coordinated by the bromine atoms and by the nitrogen atoms of the phosphane imine molecules. Pale red crystals of [Ni(PMePh₂)₄] ( 4 ) have been obtained by the reaction of [NiBr(NPMe₃)]₄ with lithium phenylacetilyde in the presence of PMePh₂. In 4 the Ni atom is distorted tetrahedrally coordinated by the phosphorus atoms of the phosphane molecules with Ni–P distances of 219.9 pm in average. 1 – 4 have been characterized by crystallographic X‐ray analyses. 1 : Space group P2₁/n, Z = 4, lattice dimensions at 193 K: a = 1566.7(2); b = 1479.9(1); c = 1960.6(2) pm; β = 105.908(9)°; R = 0.0443. 2 · 3 CH₂Cl₂: Space group P2₁/c, Z = 4, lattice dimensions at 293 K: a = 1226.0(3); b = 1614.0(3); c = 2406.0(5) pm; β = 92.34(3)°; R = 0.0703. 3 : Space group C2/c, Z = 4, latttice dimensions at 203 K: a = 1840.7(1); b = 810.1(1); c = 1607.2(2) pm; β = 94.74(1)°, R = 0.0340. 4 : Space group P1, Z = 2, lattice dimensions at 223 K: a = 1053.1(2); b = 1315.0(3); c = 1674.5(3) pm; α = 81.55(1)°; β = 79.15(2)°; γ = 84.91(2)°; R = 0.0497.     

Nickel(II)‐Complexes of Aliphatic and Aromatic Nitro Compounds: Preparation and Crystal Structures of [Ni2L(μ1,3‐O2NC6H4O)][ClO4] and [Ni2L(μ1,3‐O2P(OC6H4NO2)2)][BPh4] (L = macrocyclic hexaamine‐dithiophenolate ligand)

The dinuclear Ni^II complex [Ni₂LCl][ClO₄] ( 1 [ClO₄]), where L^2? is a 24‐membered macrocyclic hexaamine‐dithiophenolate ligand, has been examined regarding its ability to coordinate organic nitro compounds (i.e. para‐nitrophenolate, nitromethane, and bis(para‐nitrophenyl)phosphate). Complex 1 [ClO₄] reacts with para‐nitrophenolate in methanol to produce [Ni₂L(μ_1,3‐O₂NC₆H₄O)][ClO₄] ( 2 [ClO₄]), the crystal structure determination of which reveals a bridging para‐nitrophenolate ligand in its aci‐nitro resonance form. The reaction of 1 [ClO₄] with nitromethane in basic solution affords the known nitrite complex [Ni₂L(μ_1,2‐NO₂)][ClO₄] ( 3 [ClO₄]), rather than an aci‐nitromethanid complex [Ni₂L(μ_1,2‐O₂N=CH₂)]⁺ ( 4 ). The reaction of 1 [ClO₄] with bis(para‐nitrophenyl)phosphate yielded [Ni₂L(μ_1,3‐O₂P(OC₆H₄NO₂)₂)]⁺ ( 5 ), which reveals a μ_1,3‐bridging bis(para‐nitrophenyl)phosphate‐ligand.     

Structural Studies of a Copper(II) Complex with Inequivalent 2‐Acetylpyridine 3‐Piperidylthiosemicarbazonato Ligands and a Nickel(II) Complex with Different Modes of Coordination by the Two Thiosemicarbazonato Moieties of 1‐Phenylglyoxal Bis{N(4)‐diethylthiosemicarbazone}

The crystal structure of a copper(II) complex of 2‐acetylpyridine 3‐piperidylthiosemicarbazone, [Cu(Acpip)₂], indicates a tridentate, monoanionic ligand (i. e., pyridine nitrogen, imine nitrogen and thiolato sulfur atoms) and a bidentate, monanionic ligand (i. e., imine nitrogen and thiolato sulfur atoms). The stereochemistry approaches square pyramidal with the bidentate ligand occupying an apical (imine nitrogen atom) and basal (thiolato sulfur atom) position. The structure of a nickel(II) complex of 1‐phenylglyoxal N(4)‐diethylthiosemicarbazone, [Ni(Pg4DE)], has a 4‐6‐5 trichelate system rather than the 5‐5‐5 system common to bis(thiosemicarbazones). Coordination of the hydrazinic nitrogen atom of the “phenyl arm” along with the thiolato sulfur atom provides the 4‐membered chelate ring.