bluuebunny/crossref_metadata_2025_split huggingface dataset:
Distal Effect of Amide and Amino Groups on the Oxygen Activation Ability and Rate of the Redox Reaction of Simplified Analogs of Bleomycin
Authors: Arai Takayuki , Shinozuka Kazuo , Sawai Hiroaki 
Published: February 2006

Abstract
New simple bleomycin (BLM) model compounds, which bear a carbamide (1), bulky t-butyl (2), simple alkyl (3), or amino group (4) around the sixth coordination site, have been synthesized in order to study the effect of the distal substituents on the redox reaction and oxygen activation ability of the iron complexes. The carbamide group in 1 lowers the pK values of the all-amino donors of the ligand, which enhances complex formation. The oxygen activation ability of the Fe(II) complexes of 1, 2, 3, and 4, is 74, 69, 43, and 41%, respectively, of that of BLM. The rate of reduction of the Fe(III) complexes of the model compounds and BLM with a reducing agent is more than ten-times lower than that of the oxygenation and activation of the corresponding Fe(II) complexes, indicating the low turnover of the iron complexes of the model compounds and BLM in the reversible redox reaction.
Synthesis of 9-Deoxy-15-hydroxycotylenol and Its Germination-Stimulating Activity on Lettuce Seeds
Authors: Kato Nobuo , Li Feng , Mori Akira , Takeshita Hitoshi 
Published: February 2006

Abstract
Cotylenins and fusicoccins, fungal diterpenoid glycosides, are know to have identical, yet unique, plant growth-regulating activities. These compounds widen the stomatal pore, stimulate cell enlargement, break seed dormancy, and stimulate rhizogenesis. Because of these plant-hormone like activities, fusicoccin, a representative of this family, has been widely utilized in plant physiology. During the course of our study on the structure-activity relationships of this class of compounds, 9-deoxy-15-hydroxycotylenol and its 15-methoxymethyl ether were synthesized in order to clarify the role of the 9α-hydroxy group of cotylenol, a common aglycon of cotylenins. Since these cotylenol analogs retained germination-stimulating activity on lettuce seeds, it has been clarified that the 9α-hydroxy group of cotylenol is not essential for its biological activities. This finding is informative in designing useful tools for targeting the 14-3-3 protein, which has recently been identified as the binding protein of fusicoccin.
Ring-Opening and Ring-Expansion Study of 3,4-Di(1-adamantyl)-1,2-dithiete
Authors: Nakayama Juzo , Masui Nobuo , Sugihara Yoshiaki , Ishii Akihiko 
Published: February 2006

Abstract
Reduction of 3,4-di(1-adamantyl)-1,2-dithiete (2) with LiEt3BH, followed by treatment with MeI, gave (E)-1,2-di(1-adamantyl)-1,2-bis(methylthio)ethene (7-E) in 87% yield. Configuration of the double bond part of 7-E was determined by X-ray diffraction analysis. Treatment of 2 with MeLi and then with MeI also gave the same alkene 7-E in 90% yield, whereas treatment of 2 with MeLi followed by acidification afforded thermally labile (E)-1,2-di(1-adamantyl)-2-methylthioethenethiol in a good yield. Reduction of 2 with LiEt3BH followed by treatment with CS2, SOCl2, and PhBCl2 gave 4,5-di(1-adamantyl)-1,3-dithiole-2-thione, 4,5-di(1-adamantyl)-1,2,3-trithiole 2-oxide, and 4,5-di(1-adamantyl)-2-phenyl-1,3,2-dithiaborole, respectively, in moderate yields. The CuCl(I)-catalyzed decomposition of Ph2CN2 in the presence of 2 afforded 4,5-di(1-adamantyl)-2,2-diphenyl-1,3-dithiole quantitatively, whereas that of tosyl azide produced 1,2-di(1-adamantyl)-2-(p-tolylsulfonyl)iminoethane-1-thione in 10% yield.
Synthesis of Dibenzo[d,g][1,3,6]trithiocins
Authors: Maruta Teruo , Sugihara Yoshiaki , Tanaka Sanae , Ishii Akihiko , Nakayama Juzo 
Published: February 2006

Abstract
6-Acetoxy-, 6-methoxy-, 6-azido-, and 6-(methylthio)dibenzo[d,g][1,3,6]trithiocins (13, 14, 17, and 18, respectively) were synthesized by reactions of 9aH-9,10-dithia-4b-thioniaindeno[1,2-a]indene chloride (4) with appropriate nucleophiles in good yields. The trithiocin 13 was also prepared by the Pummerer reaction of dibenzo[d,g][1,3,6]trithiocin 5-oxide (12) in 97% yield. In many reactions of 4 with nucleophiles, the trimeric partial hydrolysis product, bis{o-[(dibenzo[d,g][1,3,6]trithiocin-6-yl)thio]phenyl} sulfide (15), was formed either as the major or a minor product. Structure of 15 was determined by X-ray diffraction analysis. Meanwhile, heating 4 in boiling methanol or ethanol gave the hydrolysis product, bis(o-mercaptophenyl) sulfide (16), in good yields. Condensation of 16 with benzaldehyde and pivalaldehyde gave 6-phenyl- and 6-t-butyldibenzo[d,g][1,3,6]trithiocins in good yields.
CH/π Interaction in the Crystal Structure of Organic Compounds. A Database Study
Authors: Umezawa Yoji , Tsuboyama Sei , Honda Kazumasa , Uzawa Jun , Nishio Motohiro 
Published: February 2006

Abstract
The CH/π interaction is a weak molecular force occurring between CH groups and π-groups. A study was carried out by use of the Cambridge Structural Database in order to obtain insights into the nature of the CH/π interaction and to examine its role in the crystal packing. The proportion of organic molecules bearing at least one CH/π interaction in their crystal structures has been found considerable. The CH hydrogen atoms tend to point toward the center of the aromatic ring. A number of short CH/π distances have been shown in the crystal structures of organic compounds. Moreover, the mean CH/π distance decreases as the acidity of the CH group increases. These results suggest that the CH/π interaction is not simply due to the dispersion force but involves other types of interactions, which are orientation-dependent and effective at wider ranges. It was suggested that the CH/π interaction constitutes one of the important factors in controlling the crystal packing of molecules.
Metal-Templated Macrolactamization of Triamino and Tetramino Esters. Facile Synthesis of Macrocyclic Spermidine and Spermine Alkaloids, (S)-(+)-Dihydroperiphylline, (±)-Buchnerine, (±)-Verbacine, (±)-Verbaskine, and (±)-Verbascenine
Authors: Kuroki Yoshichika , Ishihara Kazuaki , Hanaki Naoyuki , Ohara Suguru , Yamamoto Hisashi 
Published: February 2006

Abstract
The total synthesis of spermidine and spermine alkaloids, (S)-(+)-dihydroperiphylline (1), (±)-buchnerine (2), (±)-verbacine (3), (±)-verbaskine (4), and (±)-verbascenine (5), is described. The construction of macrocyclic lactams has been efficiently accomplished by the metal-templated cyclization of triamino esters and tetraamino esters. It was also found that the antimony(III) ethoxide is useful as an intermolecular amidation catalyst.
Synthesis of 2,5-Dihydro-1,2,4-oxadiazoles through Formal [3 + 2] Cycloaddition of Oxazoles with Nitrosobenzene Derivatives
Authors: Suga Hiroyuki , Shi Xiaolan , Ibata Toshikazu 
Published: February 2006

Abstract
The reactions of substituted oxazoles with nitrosobenzene gave 2-phenyl-2,5-dihydro-1,2,4-oxadiazoles regioselectively through formal [3 + 2] cycloadditions proceeding via a ringopening of oxazoles by an attack of nitrosobenzene. The reactions with 1-chloro- and 1-methyl-4-nitrosobenzenes also produced the corresponding 2,5-dihydro-1,2,4-oxadiazoles regioselectivity.
An Efficient Aerobic Oxidation of Isobutane to t-Butyl Alcohol by N-Hydroxyphthalimide Combined with Co(II) Species
Authors: Sakaguchi Satoshi , Kato Susumu , Iwahama Takahiro , Ishii Yasutaka 
Published: February 2006

Abstract
Highly selective aerobic oxidation of isobutane to t-butyl alcohol was successfully achieved by the use of a radical catalyst, N-hydroxyphthalimide (NHPI) in the presence of Co(II) salt under relatively mild conditions. The oxidation of isobutane by NHPI combined with Co(acac)2 under a pressure of air (10 atm) in benzonitrile at 100 °C gave t-butyl alcohol in high yield (84%) along with acetone (13%). The reaction is thought to proceed via hydrogen abstraction from isobutane by the phthalimidooxyl radical (PINO), which seems to be a key active species. The formation of acetone can be explained by a partial β-scission of the t-butoxy radical, generated from the redox decomposition of t-butyl hydroperoxide by cobalt ion. Alkyl-substituted butanes and pentanes were difficult to be oxidized selectively under these conditions because of easy degradation to smaller fragments of the resulting alkoxyl radical intermediates.
Relationship between the Yields of Products from Ethanol over Titanium Dioxide and the Quantity of Light
Authors: Iseda Kozo , Towata Atsuya , Watanabe Eiji , Fukaya Mitsuharu , Taoda Hiroshi 
Published: February 2006

Abstract
Acetaldehyde, acetaldehyde diethyl acetal (acetal), ethylene, hydrogen, methane, and carbon dioxide were produced from neat ethanol over TiO2 powder without metal in an Ar atmosphere under light irradiation. The yields of these products decreased in the above order. The following observation was obtained by using a filter which cut light at wavelengths below 390 nm. The yield of carbon dioxide was slightly decreased. The yield of acetaldehyde was greatly decreased at the initial irradiation, while it was slightly decreased with continuing of irradiation. The yield of acetal somewhat decreased, and that of ethylene, methane, and hydrogen roughly decreased to 1/2, 1/5, and 1/10, respectively.
Chemical Consequences of Arylnitrenes in the Crystalline Environment
Authors: Sasaki Akito , Mahé Loïc , Izuoka Akira , Sugawara Tadashi 
Published: February 2006

Abstract
UV photolysis of powdered crystals of several aryl azides at cryogenic temperatures afforded azo compounds predominantly. In the cases of p-(N-methylacetamido)phenyl azide and 2-azidobiphenyl, a CH insertion product or a carbazole was formed, competing with azo formation. These products can be considered to be formed through topotactic processes when the crystal structures are taken into account. The arylnitrenes generated in the azide crystals were monitored by ESR spectroscopy; they turned out to have extremely long half life-times, compared with those in the gas phase or in solution. Such high kinetic stabilities are ascribed to the inert environment around the generated nitrenes. The decay process of arylnitrenes in the initial stage obeyed a pseudo-first order kinetics; activation parameters were evaluated by Arrhenius plots. The activation enthalpies and entropies indicate that the diffusional processes of arylnitrenes may be the vital factors determining the kinetic stability and the product distribution in the crystalline environment.
Excited State Dynamics of Microcrystalline Acridine by Femtosecond Diffuse Reflectance Spectroscopy
Authors: Asahi Tsuyoshi , Furube Akihiro , Masuhara Hiroshi 
Published: February 2006

Abstract
The electronic structure of the excited states and triplet formation dynamics in the acridine microcrystal have been studied by femtosecond diffuse reflectance absorption spectroscopy and picosecond fluorescence spectroscopy. It was confirmed that an excimer was formed in the microcrystal within a few picoseconds after excitation. The time constant of triplet formation from the lowest excited singlet (S1) state was obtained to be about 900 ps at room temperature, which is about ten times slower than that in an aprotic solvent. Also, triplet formation was not observed up to 6 ns at 77 K. Slow intersystem crossing in the crystal was explained in terms of a selective stabilization of the 1ππ* electronic configuration due to excimer formation. An important role of intermolecular interactions on the intersystem crossing process of the crystal is discussed.
Molecular Recognition of Naphthalenedicarboxylic Acid Regioisomers by Cyclodextrins
Authors: Tan Wei Hua , Niino Noriaki , Ishikura Takahiro , Maruta Aya , Yamamoto Tatsuyuki , Matsui Yoshihisa 
Published: February 2006

Abstract
Complexation of cyclodextrins (CD’s) with some regioisomers of naphthalenedicarboxylic acid (NDC) was examined in 0.1 mol dm−3 NaHCO3 at 25 °C by means of 1H NMR spectroscopy, together with the measurement of induced circular dichroism spectra of NDC’s with the addition of CD’s. The 1H NMR spectra of 2,6- and 2,7-NDC’s showed characteristic AB-type patterns, which changed continuously with increasing CD concentration in accord with the Pople theory. The binding constants (Ka) for β-CD complexes with NDC’s increased in the order of: 1,4-NDC ≈ 1,5-NDC &lt; 1,3-NDC &lt; 1,6-NDC &lt; 2,3-NDC &lt; 2,7-NDC ≤ 2,6-NDC, indicating that β-CD is able to recognize the molecular structures of NDC’s. On the other hand, interactions of α- and γ-CD’s with NDC’s were very weak and nonspecific to NDC’s. The molecular structures of β-CD complexes with some NDC’s were estimated based on the ROESY spectra of the systems. Column chromatography of NDC’s using a β-CD-(2-chloromethyloxirane) polymer column showed that the retention volumes for NDC’s increased in the order of: 1,4-NDC &lt; 1,6-NDC &lt; 2,3-NDC &lt; 2,7-NDC &lt; 2,6-NDC, which agreed with the order the Ka values.
Molecular Mechanics Calculation of Titanium(IV) Schiff-Base Complexes
Authors: Rajan Ramalingam , Subramanian Venkatesan , Nair Balachandran Unni , Ramasami Thirumalachari 
Published: February 2006

Abstract
The force field for Ti(IV) Schiff-base complexes having the general formula Ti(Schiff-base) Cl2 (where Schiff-base = −OC6H4–CH=N–(CH2)n–N=CH–C6H4O− and n = 2, 3, 4, 5, and 6) has been generated. Using the generated force-field minimum energy conformers have been predicted for the corresponding Ti(IV) complexes. It has been shown that when n = 2 and 3, the compound prefers a trans-configuration. In the case where n = 4, 5 and 6, the total energy difference between the cis- and trans-conformers are not large enough for one to make any definite predictions about the preferred conformation. However the total energy of the trans-conformer is also lower than that of the cis-conformer in these cases.
Deswelling Kinetics of Macroporous Poly(N-isopropylacrylamide) Gel in Salt Solution
Authors: Kato Norihiro , Takahashi Fujio 
Published: February 2006

Abstract
The deswelling kinetics of a macroporous poly(N-isopropylacrylamide) gel in a NaCl solution was investigated. NaCl was used as the probe in order to trace out any hydration from the hydrated polymer chains. In the case of macroporous gel immersed in a NaCl solution, the minimum of the initial deswelling rate (v = 0.06 s−1) appeared at around 0.2—0.3 M (1 M = 1 mol dm−3) when the equilibrated gels (at 22 °C) were heated to 40 °C. The maxima of the apparent activation energy (Ea = 110 kJ mol−1) and the change in the activation entropy (ΔS313 = 80 J K−1 mol−1) were at 0.2—0.3 M NaCl. These results indicate that deswelling of the gel in a NaCl solution advanced on the condition of the following two factors. One is an electrostatic repulsion between Cl− ions below 0.2—0.3 M. Another is a salting-out effect due to NaCl above 0.2—0.3 M. The deswelling kinetics and the lower critical solution temperatures of the gels in other alkalimetal halide solutions were also measured in order to clarify the effect of the species of the cations and the anions on the interaction between the water and polymer chains.
Neutron Diffraction Studies on the Hydrogen-Bonded Structure in Concentrated Aqueous Hydrochloric Acid Solutions
Authors: Kameda Yasuo , Usuki Takeshi , Uemura Osamu 
Published: February 2006

Abstract
The neutron diffraction measurement with the H/D isotopic substitution technique has been carried out on the aqueous 21 mol% hydrochloric acid solutions, in order to investigate the short-range structure in the concentrated aqueous acid solution, in comparison with the structural information available on liquid pure water. Observed partial structure factors : aHH(Q), aXH(Q), and aXX(Q) (X: O, Cl), determined by the least-squares fitting analysis, have exhibited that the nearest-neighbor intermolecular hydrogen-bond distances, r(H···H) and r(O···H), between oxonium ion and water molecule in the 21 mol% hydrochloric acid solution were 2.02 ± 0.05 and 1.69 ± 0.02 Å, respectively; such values are much smaller than those in liquid pure water. Consequently, a strong intermolecular hydrogen bond between oxonium ion and its nearest-neighbor water molecules is concluded to be present in the concentrated aqueous hydrochloric acid solution.
Novel One-Dimensional Organic Conductor Based on Selenium-Containing Bis-Fused Tetrathiafulvalene Derivative, (TSM-TTP)(I3)5/3
Authors: Mori Takehiko , Kawamoto Tadashi , Misaki Yohji , Tanaka Kazuyoshi 
Published: February 2006

Abstract
A novel selenium-containing bis-fused tetrathiafulvalene donor, TSM-TTP (2,5-bis[4,5-bis(methylseleno)-1,3-dithiol-2-ylidene]-1,3,4,6-tetrathiapentalene) forms a 3 : 5 triiodide salt, (TSM-TTP)(I3)5/3. This salt has uniform one-dimensional columns of the donors, and is isostructural to the corresponding complex of the sulfur analog. This compound shows a high electrical conductivity, 200 S cm−1 at room temperature, and undergoes a metal-insulator transition around 20 K. Another insulating (σrt = 0.03 S cm−1) phase with trimerized columns is also obtained.
Synthesis and Structure of Palladium(II) Complexes with N(21),N(22)-Bridged Porphyrin Ligands
Authors: Takao Yuko , Takeda Tokuji , Miyashita Keiko , Setsune Jun-ichiro 
Published: February 2006

Abstract
Palladium complexes of N(21),N(22)-(etheno)-bridged porphyrins were synthesized by the reaction of palladium(II) chloride and N(21),N(22)-(etheno)-tetraphenylporphyrins or N(21),N(22)-(etheno)-octaethyl-5,22-dihydroporphyrins. The metallation proceeded via an initially produced monoprotonated porphyrin with a palladate anion. Dinuclear complexes including two PdCl2 units were preferentially produced and were converted into mononuclear complexes by a treatment with a saturated aqueous NaCl solution. Single-crystal X-ray diffraction shows the di-μ-chlorodipalladium(II) structure of the dinuclear complex, N(21),N(22)-(EtC=CEt)(TPP)(PdCl2)2·CH2Cl2·H2O (TPP = 5,10,15,20-tetraphenylporphyrin dianion). Pd(1) is coordinated by two adjacent imine nitrogens of the porphyrin as the terminal ligands and placed out of the porphyrin 4N mean plane by 1.32 Å. The distal Pd(2) is placed at a distance of 3.78 Å from the porphyrin 4N mean plane and comes close to the porphyrin ring with a dihedral angle of 139.8° between the two square planes of the Pd coordination. The NMR spectrum in solution indicated the influence of the distal Pd(2) on the porphyrin ring. The etheno bridge keeps the geometry of the 4N core of the porphyrin relatively undeformed in comparison with the previously reported methano bridge, which accounts for the enhanced stability of Pd(II) complexes.
A Pair of Trans and Cis Isomers of Platinum(II) Schiff Base Complex with N, S Chelate Containing Ferrocenyl Pendant Groups
Authors: Nagasawa Isoroku , Kawamoto Tatsuya , Kuma Hiro , Kushi Yoshihiko 
Published: February 2006

Abstract
The reaction of bis(hexafluoroacetylacetonato)platinum(II) with 2-(ferrocenyl)benzothiazoline affords trans and cis isomers of platinum(II) Schiff base complex, trans-[Pt(fabt)2] (1) and cis-[Pt(fabt)2] (2) (fabt = 2-(ferrocenylmethyleneamino)benzenethiolato). The structures of 1 and 2 have been determined by the single crystal X-ray diffraction method. Crystal data for complex 1 are triclinic with space group ; a = 15.283(15), b = 13.180(8), c = 9.847(12) Å; α = 72.91(6), β = 98.02(9), γ = 94.95(6)°; V = 1875.2(30) Å3; Z = 2. Crystal data for complex 2 are orthorhombic with space group P212121; a = 20.593(7), b = 12.300(5), c = 11.754(4) Å; V = 2977.0(18) Å3; Z = 4. The complex 1 has a trans-planar N2S2 configuration and two fabt groups take an unique umbrella conformation. On the other hand, the complex 2 has a cis-planar N2S2 configuration and two fabt groups take a helical geometry with a stepped conformation. The space group P212121, Z = 4 for 2 indicates that 2 is spontaneously resolved.
A New Active Intermediate in Monooxygenations Catalyzed by Iron Porphyrin Complexes
Authors: Murakami Tatsuya , Yamaguchi Kazuya , Watanabe Yoshihito , Morishima Isao 
Published: February 2006

Abstract
A new type of high-valent oxoiron porphyrin (3b) has been prepared by the reaction of FeIII(tdcpp) (1b) [tdcpp: 5,10,15,20-tetrakis(2,6-dichlorophenyl)porphyrin] with an oxidant such as p-nitroperbenzoic acid and pentafluoroiodosylbenzene at −90 °C in CH2Cl2 in the presence of a small amount of methanol. The UV-vis spectrum of 3b (λmax at 418 and around 550 nm) is similar to that of O=FeIV(tdcpp) (4b, λmax 419, 543 nm). However, titration of 3b by iodide ion indicates that the oxidation state of 3b is two-electron oxidized from the iron(III) state. Further, 3b catalyzes oxygenation of olefins such as styrene even at −90 °C. Possible formulation of 3b as a π-cation radical is readily ruled out by deuterium NMR observation. The solution magnetic susceptibility (μeff = 4.0 ± 0.2 μB) of 3b indicates that 3b has three unpaired electrons. These results indicate the formal description of 3b as being a high spin complex of either an O=Fe(V) porphyrin or ·O–Fe(IV) porphyrin. The same oxidation of 1b in the absence of methanol gave O=FeIV(tdcpp) π-cation radical (2b). We think the ligation of methanol causes the destabilization of iron d orbitals and eventually turns upside down the energy levels between the iron dxz, dyz orbitals and the porphyrin HOMO orbital (a2u) since the a2u orbital is stabilized by the introduction of electron-withdrawing groups on the porphyrin ring.
Studies of Organotin(IV) Derivatives of Dl-Methionine and l-Asparagine
Authors: Nath Mala , Yadav Rakesh 
Published: February 2006

Abstract
New organotin(IV) complexes of the general formula R3SnL [where R = Me, Bu, and Ph], Ph2SnL2 and Bu2SnL2 [where L = monoanion of Dl-methionine (HL-1) and l-asparagine (HL-2)] were synthesized and characterized by elemental analyses as well as molar conductance, electronic, infrared, far-infrared, 1H and 13C NMR, and 119Sn Mössbauer spectral studies. Probable structures are suggested for the complexes. Thermal studies of a few complexes have been carried out in the temperature range 25—1000 °C using the TG, DTG, and DTA techniques, indicating the formation of SnO as a residue. The complexes were tested in vitro against a wide spectrum of bacteria and fungi and found to be active. Only two complexes, Ph3SnL-1 and Ph3SnL-2, have been found to be slightly active in vivo against a multiinfection fungal model in mice.
Synthesis, Crystal Structures, and Properties of S-Bridged Pt(II)-Ni(II) Dinuclear Complexes: Conversion of Square-Planar [Ni(aet)2] to Octahedral Geometry by Forming an S-Bridged Structure with Pt(II) (aet = 2-Aminoethanethiolate)
Authors: Okamoto Ken-ichi , Yoshinari Yukie , Yamada Yasunori , Sakagami Narumi , Konno Takumi 
Published: February 2006

Abstract
The reactions of [Ni(aet)2] with [PtCl2(L)] gave a new type of S-bridged dinuclear complexes [Pt(L){Ni(aet)2(H2O)2}]2+ (aet = aminoethanethiolate; L = bpy = 2,2′-bipyridine, phen = 1,10-phenanthroline (5), dmbpy = 4,4′-dimethyl-2,2′-bipyridine). These complexes readily react with L′ to form [M(L){Ni(aet)2(L′)}]2+ (L = bpy, L′ = bpy (3), phen; L = phen, L′ = phen, bpy; L = L′ = dmbpy). A similar reaction of [Ni(aet)2] with [PtCl2(phen)] and phen gave only [Pt(phen){Ni(aet)2(phen)}]2+. The crystal structures of 3 and 5 were determined by X-ray crystallography. The Ni atoms are surrounded by two aet and a bpy or two water molecules to have an approximately octahedral geometry, forming the C2-cis(S)-[Ni(aet)2{bpy or (H2O)2}] unit. The Pt atoms have a square-planar geometry, in which two Cl atoms of the starting [PtCl2(L)] (L = bpy or phen) have been substituted by the two S atoms from the Ni(II) unit. The Pt(II) plane and the Ni(II) equatorial plane are almost coplanar, and the Pt–Ni distance is 3.4987(8) Å (3) and 3.476(4) Å (5). All of the complexes were characterized on the basis of the electronic absorption and infrared spectra and the cyclic voltammetry. The conversion of a square-planar [Ni(aet)2] to an octahedral [Ni(aet)2{(H2O)2 or (L′)}] units was also considered. In the solid state, the water molecule in [Pt(L){Ni(aet)2(H2O)2}]2+ could be readily exchanged by nitrate.