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1.
Adsorption of Fe(ClO4)3(H2O)6 onto chromatographic grade silica gel in the presence of alcohol (to be used for esterification) produces a supported reagent, Fe(ClO4)3(ROH)6/SiO2. This reagent, has been found effective for the rapid and high yield of esters, on grinding in the presence of carboxylic acids using pestle and mortar in the solid state. 相似文献
2.
Using the ligands N‐methylimidazole ( MeIm ), N‐ethylimidazole ( EtIm ), N‐propylimidazole ( PrIm ), and 1‐methyl‐1H‐1, 2, 4‐triazole ( MeTz ) three series with a total of 13 iron(II) complexes were isolated. The series comprise of the following complexes: (a) [Fe( MeIm )6](ClO4)2 ( 1 ), [Fe( EtIm )6](ClO4)2 ( 2 ), [Fe( PrIm )6](ClO4)2( 3 ), [Fe( MeTz )6](ClO4)2 ( 4 ), [Fe( MeIm )6](MeSO3)2 ( 5 ), [Fe( EtIm )6](MeSO3)2 ( 6 ), and [Fe( MeTz )6](BF4)2 ( 10 ); (b) [Fe( MeIm )4(MeSO3)2]( 7 ), [Fe( EtIm )4(MeSO3)2] ( 8 ), and [Fe( PrIm )4(MeSO3)2] ( 9 ); (c) [Fe( MeIm )4(NCS)2] ( 15 ), [Fe( EtIm )4(NCS)2] ( 16 ), and [Fe( MeTz )4(NCS)2] ( 17 ). Single crystal X‐ray diffraction studies were performed on 7 – 10 and 15 – 17 . Temperature dependent magnetic susceptibility measurements were performed on selective examples of all series, and confirmed them to be in the HS state over the range 6–300 K. DFT calculations were performed at BP86/def‐SV(P) and TPSSh/def2‐TZVPP level on all [Fe L 6]2+ complex cations and the neutral complexes 7 – 9 and 15 – 17 . Additionally the four homoleptic nickel(II) complexes [Ni L 6](ClO4)2 ( 11 : L = MeIm ; 12 : L = EtIm ; 13 : L = PrIm ; 14 : L = MeTz ) were synthesized and compounds 11 – 13 structurally characterized. UV/Vis/NIR spectroscopic measurements were carried out on all homoleptic iron(II) and nickel(II) complexes. The 10Dq values were determined to be in the range of 11547–11574 and 10471–10834 cm–1 for the iron(II) and nickel(II) complexes, respectively. 相似文献
3.
Luzian Porwol Daniel J. Kowalski Alon Henson De‐Liang Long Nicola L. Bell Leroy Cronin 《Angewandte Chemie (International ed. in English)》2020,59(28):11256-11261
We present a chemical discovery robot for the efficient and reliable discovery of supramolecular architectures through the exploration of a huge reaction space exceeding ten billion combinations. The system was designed to search for areas of reactivity found through autonomous selection of the reagent types, amounts, and reaction conditions aiming for combinations that are reactive. The process consists of two parts where reagents are mixed together, choosing from one type of aldehyde, one amine and one azide (from a possible family of two amines, two aldehydes and four azides) with different volumes, ratios, reaction times, and temperatures, whereby the reagents are passed through a copper coil reactor. Next, either cobalt or iron is added, again from a large number of possible quantities. The reactivity was determined by evaluating differences in pH, UV‐Vis, and mass spectra before and after the search was started. The algorithm was focused on the exploration of interesting regions, as defined by the outputs from the sensors, and this led to the discovery of a range of 1‐benzyl‐(1,2,3‐triazol‐4‐yl)‐N‐alkyl‐(2‐pyridinemethanimine) ligands and new complexes: [Fe(L1)2](ClO4)2 ( 1 ); [Fe(L2)2](ClO4)2 ( 2 ); [Co2(L3)2](ClO4)4 ( 3 ); [Fe2(L3)2](ClO4)4 ( 4 ), which were crystallised and their structure confirmed by single‐crystal X‐ray diffraction determination, as well as a range of new supramolecular clusters discovered in solution using high‐resolution mass spectrometry. 相似文献
4.
Heterodinuclear Ruthenium(II) Complexes of the Bridging Ligand 1,6,7,12‐Tetraazaperylene with Iron(II), Cobalt(II), Nickel(II), as well as Palladium(II) and Platinum(II) 
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下载免费PDF全文 Thomas Brietzke Alexandra Kelling Uwe Schilde Wulfhard Mickler Hans‐Jürgen Holdt 《无机化学与普通化学杂志》2016,642(1):8-13
The first heterodinuclear ruthenium(II) complexes of the 1,6,7,12‐tetraazaperylene (tape) bridging ligand with iron(II), cobalt(II), and nickel(II) were synthesized and characterized. The metal coordination sphere in this complexes is filled by the tetradentate N,N′‐dimethyl‐2,11‐diaza[3.3](2,6)‐pyridinophane (L‐N4Me2) ligand, yielding complexes of the general formula [(L‐N4Me2)Ru(µ‐tape)M(L‐N4Me2)](ClO4)2(PF6)2 with M = Fe {[ 2 ](ClO4)2(PF6)2}, Co {[ 3 ](ClO4)2(PF6)2}, and Ni {[ 4 ](ClO4)2(PF6)2}. Furthermore, the heterodinuclear tape ruthenium(II) complexes with palladium(II)‐ and platinum(II)‐dichloride [(bpy)2Ru(μ‐tape)PdCl2](PF6)2 {[ 5 ](PF6)2} and [(dmbpy)2Ru(μ‐tape)PtCl2](PF6)2 {[ 6 ](PF6)2}, respectively were also prepared. The molecular structures of the complex cations [ 2 ]4+ and [ 4 ]4+ were discussed on the basis of the X‐ray structures of [ 2 ](ClO4)4 · MeCN and [ 4 ](ClO4)4 · MeCN. The electrochemical behavior and the UV/Vis absorption spectra of the heterodinuclear tape ruthenium(II) complexes were explored and compared with the data of the analogous mono‐ and homodinuclear ruthenium(II) complexes of the tape bridging ligand. 相似文献
5.
Coro Echeverria Miguel Rubio Geoffrey R. Mitchell Anna Roig Daniel López 《Journal of Polymer Science.Polymer Physics》2015,53(11):814-821
We have succeeded in the preparation of electrospun fibers of polystyrene incorporating a metallo‐organic polymer of [Fe (II) (4‐octadecyl‐1,2,4‐triazole)3(ClO4)2]n. The obtained fibers have diameters in the range 2–4 µm and show the characteristic spin‐crossover transition associated with the metallo‐organic polymer. The structure of both, polystyrene and the metallo‐organic polymer, in the fibers was also studied. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 814–821 相似文献
6.
In this short review, we wish to present an overview of the applications of hydrated, ferric perchlorate, Fe(ClO4)3.XH2O as an available and inexpensive reagent amd catalyst in organic synthesis. 相似文献
7.
Four lanthanide supramolecular coordination compounds, [Eu(gly)2(phen)2(H2O)2](ClO4)3(phen)4 · H2O ( 1 ), [Eu2(APA)6(phen)2](ClO4)6(phen)4 · 3H2O ( 2 ), [Tb2(ABA)4(phen)4](ClO4)6(phen)4 ( 3 ), and [Eu2(AHA)4(phen)4](ClO4)6(phen)2 · 2H2O · 2C2H5OH ( 4 ) (gly = glycine, APA = 3‐aminopropionic acid, ABA = 4‐aminobutanoic acid, AHA = 6‐aminohexanoic acid, phen = 1, 10‐phenanthroline), were synthesized and characterized by single crystal X‐ray diffraction. Compound 1 has a 2‐D supramolecular layered structure of mononuclear coordination cations and free phen molecules connected via hydrogen bonding and π‐π stacking interactions. 2 forms a 3‐D supramolecular network by hydrogen bonding between binuclear coordination cations and free phen molecules, between coordination cations and lattice water molecules, and π‐π stacking interactions between free phen molecules. Compounds 3 and 4 form 2‐D supramolecular structures with π‐π stacking between coordinating phen molecules, and between free phen molecules hydrogen‐bonded to the binuclear coordination cations. The high‐resolution emission spectra show only one Eu3+ ion site in the title complexes. The aqueous solutions of the title complexes are all photochromic with the color of the solution changing from yellow to green when irradiated by mercury lamp. During the decoloration process, they return to yellow color. 相似文献
8.
Katarína Kráľová Elena Masarovičová František Šeršeň Iveta Ondrejkovičová 《Chemical Papers》2008,62(4):358-363
Synthesis and spectral characteristics of [Fe(nia)3Cl3] and [Fe(nia)3(H2O)2](ClO4)3 are described. The effect of these compounds as well as of FeCl3·6H2O on photosynthetic electron transport in spinach chloroplasts was investigated using EPR spectroscopy. It was found that
due to the interaction of these compounds with tyrosine radicals situated at the 161st position in D1 (TyrZ) and D2 (TyrD) proteins located at the donor side of photosystem (PS) II, electron transport between the photosynthetic centres PS II and
PS I was interrupted. In addition, the treatment with [Fe(nia)3(H2O)2](ClO4)3 resulted in a release of Mn(II) from the oxygen evolving complex situated on the donor side of PS II. Moreover, the effect
of the Fe(III) compounds studied on some production characteristics of hydroponically cultivated maize plants and on Fe accumulation
in plant organs was investigated. In general, the production characteristic most inhibited by the presence of Fe(III) compounds
was the leaf dry mass and [Fe(nia)3(H2O)2](ClO4)3 was found to be the most effective compound. The highest Fe amount was accumulated in the roots, and the leaves treated with
Fe(III) compounds contained more Fe than the stems. The treatment with FeCl3·6H2O caused the most effective translocation of Fe into the shoots. Comparing the effect of nicotinamide complexes, [Fe(nia)3(H2O)2](ClO4)3 was found to facilitate the translocation of Fe into the shoots more effectively than [Fe(nia)3Cl3]. This could be connected with the different structure of these complexes. [Fe(nia)3(H2O)2](ClO4)3 has ionic structure and, in addition, coordinated H2O molecules can be easily substituted by other ligands.
Dedicated to Professor Milan Melník on the occasion of his 70th birthday. 相似文献
9.
This article deals with the hitherto unexplored metal complexes of deprotonated 6,12‐di(pyridin‐2‐yl)‐5,11‐dihydroindolo[3,2‐b]carbazole (H2L). The synthesis and structural, optical, electrochemical characterization of dimeric [{RuIII(acac)2}2(μ‐L.?)]ClO4 ([ 1 ]ClO4, S=1/2), [{RuII(bpy)2}2(μ‐L.?)](ClO4)3 ([ 2 ](ClO4)3, S=1/2), [{RuII(pap)2}2(μ‐L2?)](ClO4)2 ([ 4 ](ClO4)2, S=0), and monomeric [(bpy)2RuII(HL?)]ClO4 ([ 3 ]ClO4, S=0), [(pap)2RuII(HL?)]ClO4 ([ 5 ]ClO4, S=0) (acac=σ‐donating acetylacetonate, bpy=moderately π‐accepting 2,2’‐bipyridine, pap=strongly π‐accepting 2‐phenylazopyridine) are reported. The radical and dianionic states of deprotonated L in isolated dimeric 1 +/ 2 3+ and 4 2+, respectively, could be attributed to the varying electronic features of the ancillary (acac, bpy, and pap) ligands, as was reflected in their redox potentials. Perturbation of the energy level of the deprotonated L or HL upon coordination with {Ru(acac)2}, {Ru(bpy)2}, or {Ru(pap)2} led to the smaller energy gap in the frontier molecular orbitals (FMO), resulting in bathochromically shifted NIR absorption bands (800–2000 nm) in the accessible redox states of the complexes, which varied to some extent as a function of the ancillary ligands. Spectroelectrochemical (UV/Vis/NIR, EPR) studies along with DFT/TD‐DFT calculations revealed (i) involvement of deprotonated L or HL in the oxidation processes owing to its redox non‐innocent potential and (ii) metal (RuIII/RuII) or bpy/pap dominated reduction processes in 1 + or 2 2+/ 3 +/ 4 2+/ 5 +, respectively. 相似文献
10.
Peng Cheng Lei Z. Zhang Wei‐Ming Bu Jiu‐He Peng Shi‐Ping Yan Dai‐Zheng Liao Zong‐Hui Jiang 《无机化学与普通化学杂志》2003,629(11):1996-1999
Three novel copper(II) complex [Cu2(bpa)(μ‐PhCO2)](ClO4)2 ( 1 ), [Cu2(bpa) (μ‐pyz)](ClO4)2 ( 2 ), and [Cu(Hbpa)](ClO4)2·2CH3CN ( 3 ) have been synthesized by the reaction of Hbpa with Cu(ClO4)2·6H2O in the presence and absence of exogenous ligands (where Hbpa = N, N'‐bis(picolinidene‐N‐oxide)‐2‐hydroxy‐1, 3‐diamino‐propane). Molecular structures of these compounds have been elucidated by single crystal X‐ray diffraction. 1 and 2 are both binuclear complexes in which two copper atoms are linked by the endogenous alkoxide oxygen and the exogenous benzoate and pyrazolate ligands, respectively. 3 consists of a one‐dimensional polymeric structure, in which Hbpa functions as a bridging mode. 相似文献
11.
Homoleptic Zinc(II) Complexes Based on 4′‐(2‐Thienyl)‐terpyridine: Preparation,Structures, and Properties 下载免费PDF全文
下载免费PDF全文 The homoleptic complexes ZnII(4′‐(2‐(5‐R‐thienyl))‐terpyridine)2(ClO4)2 [R = hydrogen ( 1 ), bromo ( 2 ), methyl ( 3 ), and methoxy ( 4 )] were prepared. Their structures were determined by single‐crystal X‐ray diffraction analyses, and further characterized by high resolution mass, infrared spectra (IR), and elemental analyses. Single crystal X‐ray diffraction analysis showed that ZnII ions in the complexes are both six‐coordinate with N6 coordination sphere, displaying distorted octahedral arrangements. The absorption and emission spectra of the homoleptic ZnII complexes were investigated and compared to those of the parent complex ZnII(4′‐(2‐thienyl))‐terpyridine)2(ClO4)2. The UV/Vis absorption spectra showed that the complexes all exhibit strong absorption component in UV region, moreover, complex 4 has an absorption component in the visible region. Thus, the photocatalytic activities of the complexes in degradation of organic dyes were investigated under UV and visible irradiation. 相似文献
12.
Prof. Biing‐Chiau Tzeng Tsung‐Yi Chang Sheng‐Luen Wei Dr. Hwo‐Shuenn Sheu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(16):5105-5112
A 1D double‐zigzag framework, {[Zn(paps)2(H2O)2](ClO4)2}n ( 1 ; paps=N,N′‐bis(pyridylcarbonyl)‐4,4′‐diaminodiphenyl thioether), was synthesized by the reaction of Zn(ClO4)2 with paps. However, a similar reaction, except that dry solvents were used, led to the formation of a novel 2D polyrotaxane framework, [Zn(paps)2(ClO4)2]n ( 2 ). This difference relies on the fact that water coordinates to the ZnII ion in 1 , but ClO4? ion coordination is found in 2 . Notably, the structures can be interconverted by heating and grinding in the presence of moisture, and such a structural transformation can also be proven experimentally by powder and single‐crystal X‐ray diffraction studies. The related N,N′‐bis‐ (pyridylcarbonyl)‐4,4′‐diaminodiphenyl ether (papo) and N,N′‐(methylenedi‐para‐phenylene)bispyridine‐4‐carboxamide (papc) ligands were reacted with ZnII ions as well. When a similar reaction was performed with dry solvents, except that papo was used instead of paps, the product mixture contained mononuclear [Zn(papo)(CH3OH)4](ClO4)2 ( 5 ) and the polyrotaxane [Zn(papo)2(ClO4)2]n ( 4 ). From the powder XRD data, grinding this mixture in the presence of moisture resulted in total conversion to the pure double‐zigzag {[Zn(papo)2(H2O)2](ClO4)2}n ( 3 ) immediately. Upon heating 3 , the polyrotaxane framework of 4 was recovered. The double‐zigzag {[Zn(papc)2(H2O)2](ClO4)2}n ( 6 ) and polyrotaxane [Zn(papc)2(ClO4)2]n ( 7 ) were synthesized in a similar reaction. Although upon heating the double‐zigzag 6 undergoes structural transformation to give the polyrotaxane 7 , grinding solid 7 in the presence of moisture does not lead to the formation of 6 . Significantly, the bright emissions for double‐zigzag frameworks of 1 and 3 and weak ones for polyrotaxane frameworks of 2 and 4 also show interesting mechanochromic luminescence. 相似文献
13.
Tao Liu Bing‐Wu Wang Yi‐Hong Chen Zhe‐Ming Wang Prof. Song Gao Prof. 《无机化学与普通化学杂志》2008,634(4):778-783
Two mixed‐valent disc‐like hepta‐nuclear compounds of [FeIIFeIII6(tea)6](ClO4)2 ( 1Fe , tea = N(CH2CH2O)33?) and [MnII3MnIII4(nmdea)6(N3)6]·CH3OH ( 2Mn , nmdea = CH3N(CH2CH2O)22?) have been synthesized by the reaction of Fe(ClO4)2·6H2O with triethanolamine (H3tea) for the former and reaction of Mn(ClO4)2·6H2O with diethanolamine (H2nmdea) and NaN3 for the later, respectively. 1Fe has the cationic cluster with a planar [FeIIFeIII6] core consisting of one central FeII and six rim FeIII atoms in hexagonal arrangement. The Fe ions are linked by the oxo‐bridges from the alcohol arms in the manner of edge‐sharing of their coordination octahedra. 2Mn is a neutral cluster with a [MnII3MnIII4] core possessing one central MnII atom surrounded by six rim Mn ions, two MnII and four MnIII. The structure is similar to 1Fe but involves six terminal azido ligands, each coordinate one rim Mn ion. 1Fe showed dominant antiferromagnetic interaction within the cluster and long‐range ordering at 2.7 K. The cluster probably has a ground state of low spin of S = 5/2 or 4/2. The long‐range ordering is weak ferromagnetic, showing small hysteresis with a remnant magnetization of 0.3 Nβ and a coercive field of 40 Oe. Moreover, the isofield of lines 1Fe are far from superposition, indicating the presence of significant zero–field splitting. Ferromagnetic interactions are dominant in 2Mn . An intermediate spin ground state 25/2 is observed at low field. In high field of 50 kOe, the energetically lowest state is given by the ms = 31/2 component of the S = 31/2 multiplet due to the Zeeman effect. Despite of the large ground state, no single‐molecule magnet behavior was found above 2 K. 相似文献
14.
利用水热法合成了一个结构新颖的超分子化合物[Co(μ2-ClO4)2(H2O)2]·2MA (1),晶体结构表明化合物1是靠氢键和p - p相互作用形成的独特的有机-无机杂化型三维超分子配合物。结构中存在两种不同的超分子构件：a)一维无机链通过氢键形成二维(4,4)拓扑网状构筑单元[Co(μ2-ClO4)2(H2O)2];b)三嗪环之间靠p - p相互作用形成的zigzag链状构筑单元。二者之间通过丰富的氢键和p-p相互作用最终形成了一个三维超分子结构。 相似文献
15.
Zusammenfassung Bei der Extraktion von Pr und Yb mitTBP aus Nitrat-Perchlorat-Lösung (Ionenstärke 3,5m, konstante Konzentration des Extraktionsmittels) bilden sich in der organischen Phase-außer den einfachen Tri- und Hexasolvaten-auch gemischte Nitrat-Perchlorat-Solvate folgender Zusammensetzung:Ln(NO3)2(ClO4) · 3TBP;Ln(NO3)(ClO4)2 · 3TBP;Ln(NO3)-(ClO4)2 · 6TBP;Ln(NO3)2(ClO4) · 6TBP. Die Aktivitätskoeffizienten der extrahierten Salze bleiben bei konstanter Ionenstärke unverändert, unabhängig von der Änderung des Verhältnisses ihrer Anionen.
Mit 3 Abbildungen 相似文献
Extraction of rare earths with tributyl phosphate from a nitrate-perchlorate medium
The extraction of Pr and Yb withTBP from a nitrate-perchlorate medium at an ionic strength of 3.5m and constant concentration of the extraction agent has been investigated. It was found that in the organic phase, besides the simple tri-and hexa-solvates, the mixed nitrate-perchlorate solvates of the following compositions are also formed:Ln(NO3)2(ClO4) · 3TBP;Ln(NO3)(ClO4)2 · 3TBP;Ln(NO3) · (ClO4)2 · 6TBP;Ln(NO3)2(ClO4) · 6TBP. The activity coefficients of the extracted salts, at a constant ionic strength remain unchanged, irrespective of the change of ratio between their anions.
Mit 3 Abbildungen 相似文献
16.
Some new tris(2-pyridylimine) complexes of iron(II) such as FeL3X2 (L = substituted imine ligand, 2-py-CR1=NR2, where R1 or R2=H, CH3(Me) and C4H5(Ph), X=ClO4? or NCS?, have been synthesized and their electronic structures in the solid state examined by magnetic measurement and 57Fe Mössbauer spectroscopic studies. All the perchlorate complexes FeL3(ClO4)2 are low-spin electronic ground state of Fe(II). The dithiocyanato-complexes, FeL3(NCS)2; the spin states of Fe(II) are dependent on substituent R1 and R2. The two complexes Fe(2-py-CH=NH)3(NCS)2 and Fe(2-py-CPh=NH)3(NCS)2 are spin-intermediate (S=1) and Fe(2-py-CH=NPh)3(NCS)2 shows a thermally inducing spin transition of 5T?1A1, whereas the other derivatives remain a low-spin (S=0, 1A1) ground state of Fe(II) at three temperatures of 298, 202 and 78 K. 相似文献
17.
N. V. Bausk S. B. Érenburg L. N. Mazalov L. G. Lavrenova V. N. Ikorskii 《Journal of Structural Chemistry》1994,35(4):509-516
Electronic and spatial structure of polynuclear iron(II) complexes Fe(ATr)3(ClO4)2, Fe(ATr)3(NO3)2, and Fe0.34Zn0.66(ATr)3(NO3)2 (where ATr is 4-amino-1,2,4-triazole) is investigated using EXAFS and XANES spectroscopy and X-ray fluorescent spectroscopy.
Changes in the distances to the first four coordination spheres of Fe and Zn atoms upon spin transitions induced by variations
of the anion or temperature are analyzed. It is shown that in polynuclear complexes the spin transition (from S=2 to S=0)
is accompanied by pronounced variations in the electronic and spatial structure. A mutual effect of Fe and Zn atoms was found
which alters the local environment of the low-spin Fe atoms in a magnetically diluted complex as compared to the initial one.
Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 35, No. 4, pp. 96–104, July–August, 1994.
Translated by L. Smolina 相似文献
18.
The reaction of Fe3(CO)12 with (C3H5)2NCS2K in THF at room temperature afforded a red‐brown solution. Treatment of the thus‐obtained solution with MeI and PhCH2Br afforded clusters 1 , (μ‐MeS)Fe2(CO)6(μ4‐S)Fe2(CO)6(μ‐CN(C3H5)2), and 2 , (μ‐PhCH2CO)Fe2(CO)6(μ4‐S)Fe2(CO)6(μ‐CN(C3H5)2). Their structures were unambiguously determined by X‐ray crystallography. Therefore, this methodology provides a novel route for the syntheses of spiro‐S Fe/S clusters with aminocarbyne ligands. 相似文献
19.
Zhao‐Peng Qi Qing Yuan Kai Cai Taka‐aki Okamura Wei‐Yin Sun Norikazu Ueyama 《无机化学与普通化学杂志》2010,636(11):2009-2015
The protonation and ZnII/CuII complexation constants of tripodal polyamine ligand N1‐(2‐aminoethyl)‐N1‐(1H‐imidazol‐4‐ylmethyl)‐ethane‐1,2‐diamine (HL) were determined by potentiometric titration. Three new compounds, i.e. [H3(HL)](ClO4)3 ( 5 ), [Zn(HL)Cl](ClO4) ( 6 ) and {[Zn(L)](ClO4)}n ( 7 ) were obtained by reactions of HL · 4HCl with Zn(ClO4)2 · 6H2O under different reaction pH, and they were compared with the corresponding CuII complexes reported previously. The results indicate that the reaction pH and metal ions have remarkable influence on the formation and structure of the complexes. 相似文献
20.