New N-nicotinyl and N-isonicotinyl, N′,N″-diaryl phosphorictriamides with new Er(III) complex: synthesis, spectroscopic study and crystal structures

Ten new N-nicotinyl and N-isonicotinyl phosphoramidates with formula XP(O)R₂, X?=?Nicotinamide(nia), R?=?NHCH₂Ph (1), N(CH₃)CH₂Ph (2), NHCH(CH₃)Ph (3), NH-CH₂C₄H₃O (4), NHCH₂(C₅H₄N) (5), 3-NH-C₅H₄N (6), and YP(O)R₂, Y?=?isonicotinamide(iso), R?=?NHCH₂Ph (7), N(CH₃)CH₂Ph (8), NHCH(CH₃)Ph (9), NH-CH₂C₄H₃O (10) plus one new Er(III) complex with formula Er(L)₂(NO₃)₃ (11), L?=?(iso)PO(NHCH₂C₄H₃O)₂ (10), were synthesized and characterized by elemental analysis and ¹H, ¹³C, ³¹P NMR, IR, UV?Cvis spectroscopy. Crystal structures of compounds 10 and 11 were also determined by X-ray crystallography. Interestingly, the ¹H NMR spectra of compounds 1, 2, 6, 7, 9 indicated long-range ⁿ J _P,H (n?=?5,6,7) coupling constants, in the range of 1.4?C1.9?Hz, for the splitting of pyridine ring protons with phosphorus atom. IR results showed that the ??(C=O) values of compounds 7?C10 are greater than those of compounds 1?C5 which means that isonicotinyl moiety is more electron withdrawing than nicotinyl group. X-ray outcomes revealed that in complex 11 three phosphoric triamide ligands have been connected to each Er(III); one from N_pyridine and two from P=O donor sites. One of the P=O donor ligands is mono dentate while the other one acts as a bidentate ligand and coordinates to another Er atom via its N_pyridine site. By forming complex 11 the P=O and C?CN_amide bond lengths of ligand is increased in both, mono and bi dentate, ligands while the C=O bond length is decreased to lower values. These variations are in good agreement with IR results. All H-bonds and electrostatic interactions lead to form a three-dimensional polymeric cluster in the crystal lattice of 10 and 11.     

Scheme of hydrolysis of five-coordinate chlorosilanes by X-ray diffraction data

Hydrolysis of monochelate five-coordinate chlorosilanes MeC(O)N(Me)CH₂SiMe₂Cl (Ia), L⁷CH₂SiMe₂Cl (Ib), L⁸CH₂SiMe₂Cl (Ic), PhtImCH₂SiMe₂Cl (Id), MeC(O)N(Me)CH₂SiMePhCl (IIa), and Im₅CH₂SiMePhCl (IIe), containing a monoanionic C,O-chelating ligand LCH₂ [L is an amide, n-membered lactam (L ⁿ ), imide (Im ⁿ ), or phthalimide (PhtIm) residue]. The structures of the starting chlorides and their hydrolysis products were established by means of X-ray diffraction analysis. Based on experimental and published data, a general scheme of hydrolysis of mono-C,O-chelate chlorosilanes was suggested, including initial formation of silyloxonium chlorides III and subsequent formation of disiloxane dihydrochlorides IV.     

Synthesis and characterization of glycol-modified vanadium(V) oxoisopropoxide and their oximato derivatives: sol–gel transformations of [VO(OPr i )3], [VO{OCH2CH2OCH2CH2O}{OPr i }] and [VO{OCH2CH2OCH2CH2O}{ON=C(CH3)(C4H3S-2)}] to vanadia

Reaction of [VO(OPr ⁱ )₃] (1) with [O(CH₂CH₂OH)₂] in 1:1 molar ratio in anhydrous benzene yield glycol-modified precursor, [VO{OCH₂CH₂OCH₂CH₂O}{OPr ⁱ }] (2). Further reactions of (2) with internally functionalized oximes in anhydrous benzene yield heteroleptic complexes of the type [VO{OCH₂CH₂OCH₂CH₂O}{ON=C(R)(Ar)}] (3–8) {where R=CH₃, Ar=C₄H₃O-2 (3), C₄H₃S-2 (4), C₅H₄N-2 (5); and when R=H, Ar=C₄H₃O-2 (6), C₄H₃S-2 (7), C₅H₄N-2 (8)}. All these derivatives have been characterized by elemental analyses, molecular weight measurements and spectroscopic techniques. The crysoscopic molecular weight measurement as well as FAB mass study suggests dimeric nature of (2). However, FAB mass spectrum of (4), and the crysoscopic molecular weight measurements of (3), (4), (5) and (6) indicate the monomeric behavior of the oximato derivatives (3–8). Hexa-coordination around vanadium(V) has been proposed for both monomeric and dimeric derivatives. Sol–gel transformations of (1), (2) or (4) to vanadia [(a), (b) or (c), respectively] have been carried out at low sintering temperature (600 °C). The XRD patterns of (a), (b) or (c) indicate formation of a single orthorhombic phase in all the three cases. The SEM images suggest grain like [for (a) and (b)] and rod like [for (c)] morphology of the crystallites. IR, Raman spectra as well as EDX analyses indicate formation of pure vanadia. Absorption spectra of the vanadia (b) and (c) suggest energy band gaps of 2.53 and 2.65 eV, respectively.     

Trichloro- and methyldichlorogermyl monochelates and dibromo- and dichlorogermyl bischelates derived from N,N-disubstituted amides of 2-hydroxycarboxylic acids

The reactions of GeCl₄, GeBr₄, and MeGeCl₃ with O-trimethylsilyl derivatives of N,N-disubstituted amides of 2-hydroxycarboxylic acids afforded pentacoordinate and hexacoordinate neutral (O,O)-mono- and (O,O)-bischelates. The reactions of glycolic acid derivatives with GeX₄ produced bischelates X₂Ge[OCH₂C(O)NR²R³]₂ 7a,c,d (X = Cl, R² = R³ = Me (a), (CH₂)₅ (c), (CH₂CH₂)₂O (d)) and 8a (X = Br). By contrast, the reactions of lactic and mandelic acid derivatives with GeCl₄ and MeGeCl₃ gave monochelates Cl₃Ge[OCH(R¹)C(O)NR²R³] (S)-9a–c (R¹ = Me) and Cl₂MeGe[OCH(R¹)C(O)NR²R³] 10a (R¹ = H), (S)-11a,b (R¹ = Me), and (S)-12a (R¹ = Ph) (R²R³ = (CH₂)₄ (b)), respectively. According to the X-ray diffraction data, the Ge atom in bischelates 7c,d and 8a has a coordination number 6, and its coordination polyhedron can be described as a slightly distorted octahedron. In monochelates (S)-9a-c, 10a, (S)-11a,b, and (S)-12a, the Ge atom has a coordination number 5, and its coordination polyhedron can be described as a trigonal bipyramid with two halogen atoms or one halogen atom and one ethereal oxygen atom in equatorial positions and the halogen atom and the amide oxygen atom in the axial positions. The bonds in the axial positions are somewhat longer than the corresponding bonds in tetracoordinate Ge compounds.     

Further studies on the properties and effect of high energetic ionizing radiation on copper(II) complexes: 1H NMR,electronic absorption,ESR spectra and solid electrical conductivity

The effect of energetic γ-radiation on ¹H NMR, electronic absorption, ESR spectra, differential thermal analysis (DTA) and solid state dc electrical conductivity of the ligand N-phenyl-2-(2-(phenylamino)acetyl)hydrazine carbothioamide (H₂L) and its copper(II) complexes; Cu(HL)(OAc)H₂O, Cu(HL)BrH₂O and Cu(H₂L)₂(NO₃)₂?3H₂O before and after γ-irradiation (hereafter referred to as (B), (B ₁ ), (B ₂ ), (B ₃ ) and (A), (A ₁ ), (A ₂ ), (A ₃ ), respectively) has been studied. Electronic spectral bands of the complexes after irradiation exhibited some better resolved shapes with a remarkably higher absorbance, ESR spectrum of complex Cu(HL)BrH₂O (B ₂ ) before irradiation showed isotropic spectrum with g _iso = 2.075 however, after irradiation (A ₂ ) displayed axial ESR spectrum with g _∥ > g _⊥ > 2.0023 and d _(x2?y2) ground state. DTA of the compounds reveals that γ-irradiation induced generation of new peaks as well as changes in the peak intensities. Solid state dc electrical conductivity for complexes was investigated before and after γ-irradiation. Complexes were found to be semiconductors, the activation energies (E _a) were calculated for the complexes by using the Arrhenius plot.     

Lipophilicity, electronic, steric and topological effects of some phosphoramidates on acethylcholinesterase inhibitory property

The differences in the inhibition potency of organophosphorus agents are manifestations of differing molecular properties of the inhibitors involved in the interaction with the active site of an enzyme. We studied the inhibition potency (IC₅₀) of phosphoramidates with the general formula [(CH₃)₂N]P(O)[p-NHC₆H₄-X]₂, where, X = F (1), Cl (2), Br (3), I (4), and [(CH₃)₂N]P(O)X[p-OC₆H₄-CH₃], where, X = o-NHC₆H₄-CH₃ (5), m-NHC₆H₄-CH₃ (6), p-NHC₆H₄-CH₃ (7), on human acetylcholinesterase (AchE) activity. Inhibition of hAChE was evaluated by a modified Ellman’s method, and spectrophotometric measurements. The ability of the compounds to inhibit AChE was predicted by PASS software (version 1.193). The IC₅₀ values for inhibitors 1–7 were found to be 0.19, 0.35, 0.50, 0.63, 2.70, 2.44 and 1.50 mM, respectively. In addition, logP values, by the experimental and calculated (software) methods, were found to be 1.03, 1.64, 2.17, 2.74, 2.34, 2.28 and 2.23. Finally, parameters of IC₅₀, logP, δ³¹P (phosphorus chemical shifts), σ_p (para-substituent constant), σ⁺ (electron-releasing), steric and topological effects were used for the structure-activity relationships (SAR) studies.     

Synthesis,Characterization, and Crystal Structure of Tertiary Phosphine-Substituted Diiron Propanedithiolate Complexes

As the active site models of [FeFe]-hydrogenase, two new tertiary phosphine-substituted diiron propanedithiolate complexes [(μ-PDT)Fe₂(CO)₅L] (PDT = SCH₂CH₂CH₂S, L = P(PhMe-m)₃, 1; PPh₂(CH₂CH₂CH₃), 2) have been prepared through carbonyl substitution reactions of parent complex [(μ-PDT)Fe₂(CO)₆] (A) with P(PhMe-m)₃ or PPh₂(CH₂CH₂CH₃) in the presence of the decarbonylating agent Me₃NO·2H₂O in MeCN at room temperature. The new complexes 1 and 2 were fully characterized by elemental analysis, FT-IR, ¹H, ¹³C{¹H}, and ³¹P{¹H} NMR spectroscopy, as well as for 1 by X-ray crystallography. In addition, the crystal structure of 1 has indicated that the phosphorus atom of the P(PhMe-m)₃ ligand resides in an apical position of the pseudo-square-pyramidal geometry of the tertiary phosphine-coordinated Fe₂ atom.     

Novel coordination polymers with 1,4-di(benzimidazole-1-yl)benzene modulated by an anion: Syntheses, structures and properties

Three novel coordination polymers, {[Co(L)(SO₄)(H₂O)](CH₃OH)}_∞ (1), {[Cd(L)₂(SiF₆)](H₂O)}_∞ (2) and [Zn(L)(NO₃)₂]_∞ (3), synthesized from 1,4-di(benzimidazole-1-yl)benzene (L), have been characterized by infrared spectroscopy, elemental analysis and single crystal X-ray diffraction. Compounds 1–3 exhibit different structures. Complex 1 has a 3-D diamond network containing 1-D Co^II chains connected by SO ₄ ^2? · anions; 2 has a 3-D-Po framework with 1-D porous channels along the c axis; and 3 has a 1-D zig-zag chain structure with a 2-D supramolecular network based on π-π interactions. The magnetic properties of 1 and the solid state fluorescence spectra of 2 and 3 have also been explored.     

Iron carbonyl cluster complexes with monophosphine ligands: synthesis,characterization, and crystal structure

Three new monophosphine-substituted iron carbonyl cluster complexes [(μ-PDT)Fe₂(CO)₅L] [(PDT = SCH₂CH₂CH₂S, L = P(CH₂Ph)₃, 1; P(C₆H₁₁)₃, 2; PPh₂(PhMe-p), 3)], which can be regarded as active site mimics for [FeFe]-hydrogenase, have been prepared in 40–70 % yields by reactions of the parent complex (μ-PDT)Fe₂(CO)₆ (A) with monophosphine ligands in the presence of the decarbonylating agent Me₃NO·2H₂O. All three complexes were characterized by elemental analysis and spectroscopic techniques, as well as by X-ray crystallography for complex 1. The IR spectra of the complexes reveal that the electron-donating abilities of the different monophosphine ligands follow the order PPh₂(PhMe-p) > P(C₆H₁₁)₃ > P(CH₂Ph)₃.     

First MnIII complexes with tetradentate (N2O2) Schiff bases and tricyanomethanide: synthesis,crystal structure,and magnetic properties

The first Mn^III complexes with Schiff bases and tricyanomethanide-anion were synthesized: [Mn(salen)C(CN)₃(H₂O)] (1), [Mn(5-Brsalen)C(CN)₃(H₂O)] (2), [Mn(salpn)C(CN)₃(H₂O)] (3), [Mn(3-MeOsalen)C(CN)₃(H₂O)] (4), [Mn(5-Brsalen)(MeOH)(H₂O)][C(CN)₃] (5), and [Mn(3-MeOsalpn)(H₂O)₂][C(CN)₃] (6), where SalenH₂ is N,N′-bis(salicylidene)ethylenediamine, 5-BrsalenH₂ is N,N′-bis(5-bromosalicylidene)ethylenediamine, SalpnH₂ is N,N′-bis-(salicylidene)-1,3-diaminopropane, 3-MeOsalenH₂ is N,N′-bis(3-methoxysalicylidene)-ethylenediamine, 3-MeOsalpnH₂ — N,N′-bis(3-methoxysalicylidene)-1,3-diaminopropane. The tricyanomethanide anion in complexes 1–4 acts as a the terminal ligand, whereas in complexes 5 and 6 tricyanomethanide is not coordinated by Mn^III and acts as an out-of-sphere counterion. The structures of complexes 1–4 are characterized by the formation of dimers due to hydrogen bonds between the water molecules and oxygen atoms of the Schiff bases. The Mn...Mn distances inside the dimers are 4.69–5.41 Å. Complex 6 has a zigzag chain structure consisting of the [Mn(3-MeOsalpn)(H₂O)₂]⁺ cations bound by double bridging aqua ligands. The study of the magnetic properties of complexes 1, 3, 4, and 6 showed the existence of antiferromagnetic interactions between the Mn^III ions through the system of hydrogen bonds.     

The transannular interaction germanium-nitrogen in germocanes: The influence of substituents

The reaction of RN(CH₂CH₂OH)CHR¹CR²R³OH (1-8) with a stoichiometric amount of tetrachloro(bromo)germane leads to the corresponding RN(CH₂CH₂O)(CHR¹CR²R³O)GeHal₂ (9-21). Difluorenylgermocane 22 was prepared by treatment of diethoxydifluorenylgermane with N-methyldiethanolamine. Different dialkanolamines were found to be successive precursors of dimethylgermocanes, RN(CH₂CH₂O)(CHR¹CR²R³O)GeMe₂ (23-26). The chemical properties of simple and easy to access germocanes RN(CH₂CH₂O)₂GeX₂ [X = OH, Br (28), Cl (29)] were studied and the difluoro (27), haloalkoxy (30-32), and dialkoxy (33, 34) derivatives were prepared. The structures of the compounds 16, 20-22, and 26 were confirmed by X-ray diffraction and the structural features in solution of 23 and 26 were studied by NMR spectroscopy (NOEs). The relationship between the nature of substituents at different positions of the germocane skeleton and the strength of the intramolecular Ge ← N bond is discussed.     

Dinuclear nickel(II) complexes with Schiff base ligands: syntheses, structures and bio-relevant catalytic activities

Three Ni(II) complexes of cresol-based Schiff-base ligands, namely [Ni₂(L¹)(NCS)₃(H₂O)₂], (1) [Ni₂(L²)(CH₃COO)(NCS)₂(H₂O)] (2) and [Ni₂(L³)(NCS)₃] (3), (where L¹ = 2,6-bis(N-ethylpyrrolidineiminomethyl)-4-methylphenolato, L² = 2,6-bis(N-ethylpiperidineiminomethyl)-4-methylphenolato and L³ = 2,6-bis{N-ethyl-N-(3-hydroxypropyl iminomethyl)}-4-methylphenolato), have been synthesized and structurally characterized by X-ray single-crystal diffraction in addition to routine physicochemical techniques. Density functional theory calculations have been performed to understand the nature of the electronic spectra of the complexes. Complexes 1?C3 when reacted with 4-nitrophenyl phosphate in 50:50 acetonitrile?Cwater medium promote the cleavage of the O?CP bond to form p-nitrophenol and smoothly convert 3,5-di-tert-butylcatechol (3,5-DTBC) to 3,5-di-tert-butylquinone (3,5-DTBQ) either in MeOH or in MeCN medium. Phosphatase- and catecholase-like activities were monitored by UV?Cvis spectrophotometry and the Michaelis?CMenten equation was applied to rationalize all the kinetic parameters. Upon treatment with urea, complexes 1 and 2 give rise to [Ni₂(L¹)(NCS)₂(NCO)(H₂O)₂] (1??) and [Ni₂(L²)(CH₃COO)(NCO)(NCS)(H₂O)] (2??) derivatives, respectively, whereas 3 remains unaltered under same reaction conditions.     

Three new Cu(II)-Ln(III) heterometallic coordination polymers constructed from quinolinic acid and nicotinic acid: Synthesis, structures, and magnetic properties

Three new Cu(II)-Ln(III) heterometallic coordination polymers based on two N-heterocyclic carboxylic ligands, {[LnCu(L¹)₂(L²)(H₂O)₂]·mH₂O} _n (Ln = La(1), Nd(2), Gd(3), m = 2 (for 1), 1 (for 2, 3), H₂L¹ = quinolinic acid, HL² = nicotinic acid), have been synthesized and characterized. 1 has a two-dimensional (2D) layer structure with a Schl?fli symbol of (4⁴.6²), while complexes 2 and 3 are isostructural and have three-dimensional (3D) structures with a Schl?fli symbol of (3.4.5)₂(3².4².5².6¹⁴.7⁴.8³.9)(3².6³.7) of 3-nodal net. Magnetic investigations suggest that antiferromagnetic coupling exists between Nd^III and Cu^II in 2, while weak ferromagnetic coupling between Gd^III and Cu^II in 3. The difference of magnetic properties between 2 and 3 has been discussed.     

Crystal structures and luminescence of a series of cadmium(II) complexes based on isophorone derivative containing imidazolyl

Three new complexes, [CdL₂(CH₃COO)₂(H₂O)₂] (I), CdL₂Br₂ (II), CdL₂I₂ (III), have been successfully synthesized by self-assembly of corresponding metal salts with (E)-2-(3-(4-(1H-imidazole-1-yl)styryl)-5,5-dimethylcyclohex-2-enylidene)malononitrile (L). The structures of the complexes were determined by single crystal X-ray diffraction analysis (CIF file CCDC nos. 957831 (I), 957792 (II), 957832 (III)). In complex I, central metal is six-coordinated and the crystal packing shows a 3D supramolecular framework. Complexes II and III display the similar 2D supramolecular structures in which the central metals are four-coordination. The luminescent properties were investigated.     

Über die Synthese von 1,3-Dihydro-3-(2-dimethylaminoäthyl)-1-(3-thienyl)-benzimidazol-2-onen

The synthesis of 1-(3-thienyl)-benzimidazol-2-ones (3 a and4), described in an earlier paper¹, has been further investigated. The Na-salt of3 a is converted to a benzimidazolone substituted in position 3 (3 b). Dehydrogenation of the thiophene nucleus of3 a with chloranil yields5 a, which undergoes substitution in position 3 with Cl(CH₂)₂N(CH₃)₂ to give5 b. Monochlorination of5 a yields5 c, the structure of which is confirmed by¹H-NMR-spectroscopy.5 d is obtained by reaction of the Na-salt of5 c with Cl(CH₂)₂N(CH₃)₂.      

The conditions of formation of heterometallic complexes in the GeCl4 (SnCl4)-citric acid-M(CH3COO)2-H2O systems. The crystal and molecular structures of [M(H2O)6][Ge(HCit)2] · 4H2O (M = Mg, Mn, Co, Cu, Zn) and [M(H2O)6][Sn(HCit)2] · 4H2O (M = Mg, Co, Ni)

Fourteen bis(citrato)germanates(IV) and bis(citrato)stannates(IV) were prepared, in particular, [M(H₂O)₆][Ge(HCit)₂] · 4H₂O (M = Mg (I), Mn (II), Fe (III), Co (IV), Ni (V), Cu (VI), Zn (VII)) and [M(H₂O)₆][Sn(HCit)₂] · nH₂O (M = Mg, n = 4 (VIII); Mn, n = 2 (IX); Fe, n = 4 (X); Co, n = 4 (XI); Ni, n = 4 (XII); Cu, n = 4 (XIII); Zn, n = 3 (XIV)) (H₄Cit is citric acid). The purity and the composition of the products were determined by a set of physicochemical methods including elemental analysis, thermogravimetry, and IR spectroscopy. The structures of I, II, IV, VI, VII, VIII, XI, and XII were determined by X-ray diffractometry. All eight crystals composed of centrosymmetrical octahederal [M(H₂O)₆]²⁺ cations, [Ge(HCit)₂]^2? (or [Sn(HCit)₂]^2?) anions, and crystal water molecules are isostructural. The structural units in I, II, IV, VI, VII, VIII, XI, and XII are connected by systems of hydrogen bonds to form a three-dimensional framework.     

Copper(II), iron(III) and cobalt(III) complexes of the pendent-arm cyclam derivative 6,6,13-trimethyl-13-amino-1,4,8,11-tetraazacyclotetradecane

The interaction of Cu(II), Fe(III) and Co(III) with 6,6,13-trimethyl-13-amino-1,4,8,11-tetraazacyclotetradecane (L ³ ) incorporating a pendent amine group has led to isolation of the new octahedral complexes [Cu(HL ³ )(ClO₄)₂]Cl·H₂O (1), [Fe(L ³ )Cl](S₂O₆)·H₂O (2), [Co(L ³ )Cl](ClO₄)_1.5Cl_0.5·0.25H₂O (3), [Co(HL ³ )Cl₂](ClO₄)₂·H₂O (4) and [Co(L ³ )Cl]₂(S₂O₄)(ClO₄)₂ (5). In (1) the copper ion occupies the macrocyclic cavity of protonated (–NH₃ ⁺) L ³ which is present in its trans-III configuration; weakly bound ClO₄ ^? ligands occupy the axial positions. The X-ray structure of (2) showed that Fe(III) occupies the N₄-macrocyclic cavity of L ³ in a trans-III configuration, with the pendent amine group binding in an axial position. The remaining axial position is occupied by a Cl^? ligand. Chromatography of the product obtained from the reaction of Na₃[Co(CO₃)₃] with L ³ yielded three fractions. Fraction 1 yielded crystals (3) composed of three crystallographically independent species incorporating cations of type [Co(L ³ )Cl]²⁺ with very similar structures; in each case the macrocyclic ring nitrogens of L ³ are bound to the Co(III) in an asymmetric cis-fashion. Fraction 2 yielded the trans-III octahedral cationic complex (4) incorporating L ³ in its protonated form. The Co(III) complex (5) from fraction 3 shows a different coordination arrangement to the products from fractions 1 or 2. The macrocyclic ring coordinates in its trans-III form, but the axial sites in this case are occupied by the pendent-NH₂ group and a Cl^? ligand.     

Syntheses, crystal structures, and characterization of four homochiral coordination polymers based on two chiral reduced Schiff base ligands

Four homochiral coordination polymers incorporating two chiral reduced Schiff base ligands, namely, [Cu(L¹)(H₂O)]·H₂O (1), [Zn₂(L²)₂] (2), [Co(L²)(H₂O)] (3), and [Ni(L²)(H₂O)] (4) (H₂L¹ = N-(4-carboxyl)benzyl-l-alanine, H₂L² = N-(4-carboxyl)benzyl-l-leucine) have been obtained by hydrothermal methods and characterized by physico-chemical and spectroscopic methods. X-ray crystallographic analysis reveals that complex 1 exhibits a chain structure with 1D channels. Complexes 2–4 all are 3D network structures with 1D channels in which the isobutyl group of the ligand points toward to the channel. Complex 2 displays strong photoluminescent emission in the purple region.     

Scandium terminal imido complex induced intramolecular C–N bond cleavage and transformation

<正>1 X-ray crystallography Suitable single crystal of 2 was sealed in a thin-walled glass capillary, and data collection was performed at 293(2) K on a Bruker SMART diffractometer with graphite-monochromated Mo Kα radiation(λ = 0.71073 ). Suitable single crystals of 3and 4 were mounted under nitrogen atmosphere on a glass fiber, and data collection was performed at 133(2) K on a Bruker APEX2 diffractometer with graphite-monochromated Mo Kα radiation(λ = 0.71073 ). The SMART program package was used to determine the unit cell parameters. The absorption correction was applied using SADABS. The structures were solved     

Ni(II) complexes with optically active bis(menthane), pinano-para-menthane ethylenediaminodioximes and pinano-para-menthane, bis(pinane) propylenediaminodioximes: Synthesis, structures, and properties

Reactions of Ni(NO₃)₂ · 6H₂O) in EtOH(iso-PrOH) with optically active bis(menthane) ethylene-diaminodioxime (H₂L¹), pinano-para-menthane ethylenediaminodioxime (H₂L²), pinano-para-menthane propylenediaminodioxime (H₂L³) and bis(pinane) propylenediaminodioxime (H₂L⁴) were used to synthesize [Ni(H₂L¹)NO₃[NO₃ · 2H₂O (I), [Ni(HL²)]NO₃ (II), [Ni(HL³)]NO₃ (III), and [Ni(HL⁴)]NO₃ (IV). X-ray diffraction study of paramagnetic complex I (μ_eff = 3.04 μB and diamagnetic complexes II and III revealed their ionic structures. A distorted octahedral polyhedron N₄O₂ in the cation of complex I is formed by the N atoms of tetradentate cycle-forming ligand, i.e., the H₂L¹ molecule, and the O atoms of the NO ₃ ^? anion acting as a bidentate cyclic ligand. In the cations of complexes II and III, containing a pinane fragment, the coordination core NiN₄ has the shape of a distorted square formed on coordination of tetradentate cycle-forming ligands, i.e., anions of the starting dioximes. The structure of diamagnetic complex IV is likely to be similar to the structures of complexes II and III.