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Polyhedral Ramsey Numbers
PublikacjaGiven two polygons or polyhedrons P1 and P2, we can transform these figures to graphs G1 and G2, respectively. The polyhedral Ramsey number Rp(G1,G2) is the smallest integer n such that every graph, which represents polyhedron on n vertices either contains a copy of G1 or its complement contains a copy of G2. Using a computer search together with some theoretical results we have established some polyhedral Ramsey numbers, for example...
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Lead(II) coordination polymers with imidazole-4- and pyrazole-3-carboxylate isomeric linkers: Structural diversity and luminescence properties
PublikacjaUsing 1H-imidazole-4-carboxylic acid (4imCOOH) and 1H-pyrazole-3-carboxylic acid (3pyrCOOH) coordination polymers [Pb(4imCOO)2(H2O)]n (1) and [Pb2(3pyrCOO)4]n (2) were constructed. Obtained polymers were characterized via FT-IR, X-ray, PL and TG methods. The coordination polyhedron around Pb(II) in 1 is described as distorted pentagonal pyramid with hemidirected coordination sphere (based on DFT calculations). Compound 2 consists...
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Synthesis, coordination properties and biological activity of vanadium complexes with hydrazone Schiff base ligands
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Metal–metal interactions in bent cyano-bridged trinuclear octacyanomolybdate(IV)–platinum(IV) complexes
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PF5 and PCl5 interacting with water – Comparative study at the molecular level
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Stability of the TinF4n+1− and GenF4n+1− superhalogen anions and the acidity of the HTi F4+1 and HGe F4+1 (n = 1–3) superacids
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Complexes of heteroscorpionate trispyrazolylborate ligands. Part XIII: Molybdenum complexes of hydrobis(5-methyl-3-phenylpyrazolyl)(3-methyl-5-phenylpyrazolyl)borate, hydrotris(3-(2-thienyl)-5-methylpyrazolyl)borate and tetranuclear molybdenum(V) complex of hydrotris(3,5-dimethylpyrazolyl)borate
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The X-ray crystallographic structures, spectral and magnetic properties of nickel(II), copper(II) and cobalt(II) complexes with tetra(3-iso-propylpyrazol-1-yl)borate
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A new complex compound of chromium(III) with 5-aminopyridine-2-carboxylate anions – Structure, physicochemical and catalytic properties
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Iminodiacetate complex of cobalt(II) – Structure, physicochemical characteristics, biological properties and catalytic activity for 2-chloro-2-propen-1-ol oligomerization
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The oxydiacetate and iminodiacetate complexes of oxidovanadium(IV) as the new series of the catalysts for the oligomerization of beta-olefin derivatives
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The Suzuki cross-coupling reaction for the synthesis of porphyrazine possessing bulky 2,5-(biphenyl-4-yl)pyrrol-1-yl substituents in the periphery
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Photochemical and spectral characterization of peripherally modified porphyrazines
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Porphyrazine with bulky 2-(1-adamantyl)-5-phenylpyrrol-1-yl periphery tuning its spectral and electrochemical properties
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Synthesis and photochemical characteristics of novel tribenzoporphyrazines possessing peripherally annulated tetrahydrodiazepine and diazepine rings
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Photophysical properties and photocytotoxicity of novel phthalocyanines – potentially useful for their application in photodynamic therapy
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Synthesis, characterization and spectroscopic properties of novel periphery – functionalized unsymmetrical porphyrazines containing mixed dithienylpyrrolyl and dimethylamino groups
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(Cyclopentadienyl){(N,N-dimethylaminoethyl)cyclopentadienyl} complexes of zirconium: Crystal structure of [(η5-C5H5)(η5-C5H4CH2CH2NHMe2)ZrCl2]2[ZrCl6]
Publikacja(C5H5)ZrCl3 reaguje z [C5H4-CH2CH2NMe2]Li dając polimer koordynacyjny {(C5H5)(C5H4-CH2CH2NMe2)ZrCl2}n, który z kolei w reakcji z HCl daje żółtozielone kryształy [(η5-C5H5)(η5-C5H4CH2CH2NHMe2)ZrCl2]2[ZrCl6]. Ten ostatni związek został scharakteryzowany za pomocą widm NMR oraz przy użyciu rentgenowskiej analizy strukturalnej. Utworzenie w/w związku wskazuje na oderwanie grup C5H5 oraz C5H4-CH2CH2NMe2 od centrum metalicznego Zr(IV).
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The new type of [Zr6(μ3-O)4 (μ3-OH)4] cluster core: Crystal structure and spectral characterization of [Zr6O4(OH)4(OOCR)12] (R = Bu^t^,C(CH3)2Et)
PublikacjaSześciojądrowe oxo karboksylowe kompleksy cyrkonu(IV) zostały otrzymane z Zr(OR')4 i odpowiednich kwasów organicznych HOOCR (R=t-Bu, CMe2Et) w stosunku molowym 1:2. Struktury krystaliczne dwóch związków o wzorze [Zr6O4(OH)4(OOCR)12] (1 dla R=t-Bu i 2 dla R=-CMe2Et) zostały rozwiązane w grupie przestrzennej R-3. Substancje zostały przebadane termograwimetrycznie (TGA/DTA) oraz przy użyciu spektroskopii w podczerwieni ze zmienną...
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Syntheses and crystal structures of lithium derivatives of diphosphanes R2P-P(SiMe3)Li·3L, R = Ph, iPr and iPr2N, L = THF or DME
PublikacjaW wyniku reakcji R2P-P(SiMe3)2 z BuLi w THF lub DME powstają pochodne litowe difosfanów R2P-P(SiMe3)Li·3L. Dla R = iPr oraz iPr2N powstają sole R2P-P(SiMe3)Li·3THF, w których atom litu jest czterokrotnie koordynowany a dla R = Ph powstaje sól [Li·3DME]+[Ph2P-PSiMe3]-, która posiada budowę jonową. W reakcji BuLi z Ph2P-P(SiMe3)2 powstają znaczne ilości produktów ubocznych: Ph2P-PPh2 i LiP(SiMe3)2.
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Lower rim substituted p-tert-butyl-calix[4]arene. Part 17. Synthesis, extractive and ionophoric properties of p-tert-butylcalix[4]arene appended with hydroxamic acid moieties
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Lower rim substituted p-tert-butyl-calix[4]arene. Part 16. Synthesis of 25,26,27,28-tetrakis(piperidinylthiocarbonylmethylene)-p-tert-butylcalix[4]arene and its interaction with metal ions
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Copper binding by the cystatin C fragment. The role of histidine residues
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Structural, physico-chemical and antioxidant characteristics of 2,2′-bipyridyl(iminodiacetato)oxidovanadium(IV) dihydrate
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Structural characterization and biological properties of a new dinuclear oxidovanadium(IV) N -(phosphonomethyl)iminodiacetate complex with the 4-amino-2-methylquinolinium cation
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Structure and characterization of physicochemical and magnetic properties of new complex containing monobridged oxygen copper(II) dinuclear cation
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Crystal structure, DFT-study and NLO properties of the novel copper(I) nitrate π,σ-coordination compound based on 1-allyl-3-norbornan-thiourea
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DFT and NBO theoretical study of protonation of tri-tert-butoxysilanethiol and its anion
PublikacjaWykonano obliczenia kwantowo-chemiczne metodą DFT dla tri-tert-butoksysilanotiolu oraz jego protonowanych i deprotonowanych form, zarówno na atomie tlenu jak i siarki. Przeanalizowano bilans energetyczny dla protonowania anionu w próżni i w fazie wodnej (stosując model IPCM). Zaobserwowano skrócenie wiązania Si-S w wyniku protonowania na atomie tlenu. Zmiany długości wiązań Si-O i Si-S zostały zinterpretowane w oparciu o analizę...
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Synthesis of novel dinuclear ruthenium polypyridine dye for dye-sensitized solar cells application
PublikacjaA new dinuclear ruthenium(II) polypyridine complex has been successfully synthesized. The new compound has been characterized by spectroscopic and electrochemical methods. Its potential application as a sensitizing dye in dye-sensitized solar cells has been checked under AM 1.5 G irradiation conditions (100 mW cm−2) and its performance was compared to that of a commercially available mononuclear analogous dye. The overall light-to-electricity...
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Lower rim substituted p-tert-butyl-calix[4]arene. Part 17. synthesis, extractive and ionophoric properties of p-tert-butylcalix[4]arene appended with hydroxamix acid moieties
PublikacjaThe synthesis and characterization of four p-tert-butylcalix[4]arene-hydroxamic acidc are reported. The dependence of the metal ion binding, assessed by liquid extraction of the metal nitrates from water into dichloromethane in individual and competitive experiments, on the ligand structure, is presented. The results showed that those ligands could be successfully used in separation process of trnasition and heavy metals often...
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General route for the synthesis of terminal phosphanylphosphido complexes of Zr(IV) and Hf(IV): Structural investigations of the first zirconium complex with a phosphanylphosphido ligand
PublikacjaReactions of R2P-P(SiMe3)Li with [Cp2MCl2] (M = Zr, Hf) in hydrocarbons yield the related terminal phosphanylphosphidocomplexes [Cp2M(Cl){(Me3Si)P-PR2-jP1}] (R = iPr and tBu). The solid state structures of [Cp2M(Cl){P(SiMe3)-PiPr2-jP1}] (M = Zr, Hf) were established by single crystal X-ray diffraction studies. The phosphido-P atoms adopt almost planar geometries and the phosphanyl P atoms adopt pyramidal geometries. The reaction...
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Nickel(II) tri-tert-butoxysilanethiolates with N-heterocyclic bases as additional ligands: Synthesis, molecular structure and spectral studies
PublikacjaW publikacji przedstawiono metodę syntezy trzech kompleksów silanotiolanowych z takimi N-heterocyklicznymi zasadami jak: pirydyna, 2-metylopirydyna i 3,5-dimetylopirydyna. Dla tych kompleksów przeprowadzono badania X-Ray, analizy elementarnej. Przy pomocy rentgenowskiej analizy strukturalnej wykazano różną koordynację atomu centralnego - niklu.
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Binuclear Co(II), Zn(II) and Cd(II) tri-tert-butoxysilanethiolates. Synthesis, crystal structure and spectroscopic studies.
PublikacjaA series of Co(II), Zn(II) and Cd(II) complexes have been synthesized in reaction of respective metal tri-tert-butoxysilanethiolates with pyrazine 1 and 2 and 1,2-bis(2-pyridyl)ethylene 3–5. All compounds have been characterized by single-crystal X-ray structure determination, elemental analysis, FT-IR and thermogravimetry. Obtained complexes are bimetallic with the formula of [M{SSi(OtBu)3}2(μ-L)]2 and metal ions bridged by N,N′-spacer....
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Synthesis, structure characterization and thermal propertiesof [Zr<sub>6</sub>(μ<sub>3</sub>-O)<sub>4</sub>(μ<sub>3</sub>-OH)<sub>4</sub>(OOCCH<sub>2</sub><sup>t</sup>Bu)<sub>9</sub>(μ<sub>2</sub>-OH)<sub>3</sub>]<sub>2</sub>
PublikacjaTytułowy związek otrzymano w reakcji Zr(OiPr)4 z nadmiarem kwasu 3,3-dimetylobutyrowego. Rentgenowska analiza strukturalna została wykonana w temperaturze 103 i 153K. Struktury zawierają dimery podjednostek o wzorze: [Zr6(μ3-O)4(μ3-OH)4-(OOCCH2tBu)9] połączonych 6 mostkującymi grupami μ2-OH. Analiza zmiennotemperaturowych...
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Mixed-ligand complexes of zinc(II), cobalt(II) and cadmium(II) with sulfur, nitrogen and oxygen ligands. Analysis of the solid state structure and solution behavior. Implications for metal ion substitution in alcohol dehydrogenase
PublikacjaScharakteryzowano strukturę heteroleptycznych kompleksów cynku(II), kobaltu(II) i kadmu(II) z 2-(2'-hydroksyetylopirydyną), tri-tert-butoksysilanotiolem i metanolem. Przy pomocy widm UV-Vis i NMR stwierdzono szybką wymianę N-liganda w roztworach tych kompleksów. Wyznaczono przesunięcia 15N NMR 2-(2'-hydroksyetylopirydyny) w kompleksach cynku(II) i kadmu(II). Na podstawie widm w podczerwieni i obliczeń DFT oszacowano względną moc...
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Copper(II) complexes with substituted imidazole and chlorido ligands: X-ray, UV-Vis, magnetic and EPR studies and chemotherapeutic potential
PublikacjaCrystal structures, UV-Vis and EPR spectra and magnetic properties of four copper(II) complexes with chloride anions and 4-methylimidazole, 2-ethylimidazole, 2-isopropylimidazole or 2-ethyl-4-methylimidazole are described. In the solid state three of the complexes are mononuclear and one complex with 2-ethylimidazole is binuclear with bridging chlorido ions. UV-Vis spectra of the methanolic solutions of the complexes show LMCT...
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Syntheses and structures of the first terminal phosphanylphosphido complexes of molybdenum(IV)
PublikacjaThe reactions of R2P-P(SiMe3)Li (R = tBu, iPr2N) with [Cp2MoCl2] yield terminal phosphanylphosphido complexes formally via the insertion of the phosphinidene P-atom into the C - H bond of a cyclopentadienyl ring and the migration of the hydrogen atom or SiMe3 moiety to the molybdenum centre. Solid state structures of [Cp(C5H4P-PtBu2)MoH], [Cp(C5H4P-PtBu2)Mo(SiMe3)] and [Cp{C5H4P-P(NiPr2)2}Mo(SiMe3)] were established by single crystal...
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Synthesis, crystal structure and spectroscopic characterization of new anionic iridium(III) complexes and their interaction with biological targets
PublikacjaThe synthesis and characterisation of new anionic iridium(II) complexes (NH4)2[IrCl4(κ2N,N’-H2biim)]2 · 5H2O (1) and ((CH3)2NH2)[IrCl4(κ2N,N’-PyBIm)] · H2O (2) are presented in this article. Spectroscopic methods (1H, 13C and 15N NMR, FTIR, UV-Vis) were used to characterize these new complexes. Solid-state structural analysis (SC-XRD) of complexes 1 and 2 shows a slightly distorted octahedral geometry of Ir(III) ions, which is...
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Sulfonamides with hydroxyphenyl moiety: Synthesis, structure, physicochemical properties, and ability to form complexes with Rh(III) ion
PublikacjaSulfonamides are the first successfully synthesized antimicrobial drugs. The mechanism of sulfonamides’ antimicrobial action involves competitive inhibition of folic acid synthesis and prevention of the growth and reproduction of bacteria. Even though they have been applied in therapy for more than 75 years, sulfonamides are still the drugs of choice for the treatment of various diseases. The aim of this work was to synthesize...
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Nitrate and nitrite silver complexes with weakly coordinating nitriles
PublikacjaSimple system of weak nitrile ligands and silver nitrite/nitrate allowed the formation and isolation of coordination compounds of diverse nuclearity and dimensionality. The extension of the network does not enhance the luminescent properties of the ligands however it gives rise to the new MLCT bands in the visible region.
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Novel complexes possessing Hg–(Cl, Br, I)⋯O=C halogen bonding and unusual Hg₂S₂(Br/I)₄ kernel. The usefulness of τ₄′ structural parameter
PublikacjaOne mononuclear and two binuclear Hg(II) complexes have been synthesized and characterized by X-ray diffraction, ATR IR and Hirshfeld surface analysis. Single-crystal X-ray diffraction showed that binuclear compounds are centrosymmetric and isostructural. All complexes form bifurcated intermolecular N–H···O hydrogen bonds that contribute to a formation of the centrosymmetric dimers. In binuclear complexes, sulfur atoms of thiourea...
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Lower Rim Substituted p-tert-Butyl-Calix[4]arene. Part 16. Synthesis of 25, 26, 27, 28-tetrakis(piperidinethiocarbonylmethylene)-p-tert-butylcalix[4]arene and its interaction with metal ions
PublikacjaThe synthesis, characterisation and X-ray crystal structures of p-tert-butyl-calix[4]arenethioamide L and its complex with lead L-Pb2+ is reported. The cation-binding properties in solution have been assessed by liquid-liquid extraction of the metal picrates from water into dichloromethane and by stability constants determination in acetonitrile using UV-absorption spectrophotometry or potentiometry. The compound was used as active...
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Copper(II) complexes of 7-amino-2-methylchromone and 7-aminoflavone: Magneto-structural, spectroscopic and DFT characterization
PublikacjaFour new complexes of copper(II) consisting of two different chromone derivatives with carbonyl and amine donor atoms: 7-aminoflavone (L1) and 7-amino-2-methylchromone (L2), were synthesized and characterized by X-ray diffraction, UV–Vis, FT-IR, EPR spectroscopy, MS and elemental analysis. In all four compounds, the chromone derivatives were found to act as monodentate O- or N-ligands. The structural characteristics of 1a and...
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Structural motifs in the Cu(II), Mn(II) and Zn(II) complexes based on N,N,N-donor dipodal or N,N,N,N-donor tripodal ligands obtained in situ: Synthesis, crystal structures and xanthine oxidase inhibition properties
PublikacjaA series of four novel transition metal complexes, [Cu(NCS)2L1] (1), [Mn(NCS)2L1] (2) where L1 = bis(1-(3,5-dimethylpyrazolyl)methyl)amine, [Mn(NCS)2L2] (3) and [Zn(NCS)L2]2[Zn(NCS)4] (4) where L2 = tris(1-(3,5-dimethylpyrazolyl)methyl)amine, has been obtained in situ by a one-step, one-pot synthetic path starting from 1-hydroxymethyl-3,5-dimethylpyrazole (L). The isolated complexes were fully characterised by elemental analysis,...
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Synthesis, physicochemical and theoretical studies on new rhodium and ruthenium dimers. Relationship between structure and cytotoxic activity
PublikacjaTwo dimeric compounds of the general formulae (Et3NH)2[Rh2(μ2-L)4Cl2] (1) (where L = thiophene-2-carboxylate) and [((η6-p-cymene)Ru)2(μ-Cl)3]PF6 (2) have been synthesized using a new method. The unique anionic complex 1 (space group P bca) has octahedral coordination in which the equatorial positions are occupied by the oxygen atoms of four thiophene-2-carboxylates in a paddle wheel fashion. In complex 2 (space group ), each Ru(II)...
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Coordination polymers and molecular structures among complexes of mercury(II) halides with selected 1-benzoylthioureas
PublikacjaSix new 1-benzoyl-3-phenylthiourea and 1-benzoyl-3-(2-methylphenyl)thiourea complexes of mercury( II) were obtained in the reactions of the ligands with HgX2 in methanol (X = Cl, Br, I). Their structures, determined by single-crystal X-ray diffraction analysis, exhibit different stoichiometries and molecular organization. Coordination centers adopt more or less distorted tetrahedral geometry (five structures) or distorted trigonal...
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Comparison of the coordination geometries of Zn(II) and Cd(II) ions in complexes with water, methanol and bulky aryloxysilanethiolate ligands
PublikacjaZinc and cadmium complexes containing silanethiolate anions and methanol or water were synthesized and characterized by X-ray diffraction, FT-IR and NMR spectroscopy, and DFT calculations. Contrary to zinc, the cadmium ion utilizes very weak donors to complete its coordination sphere; it forms contacts to phenyl rings of the silanethiolate ligand. Two zinc analogs of the general formula [Zn{SSi(OAr)3}2(L)2] where L = CH3OH (2)...
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Proton transfer and hydrogen bonds in supramolecular, self-assembled structures of imidazolium silanethiolates. X-ray, spectroscopic and theoretical studies
PublikacjaThe reaction of 1-methylimidazole, 2-ethyl-4-methylimidazole and 2-ethylimidazole with tris(2,6- diisopropylphenoxy)silanethiol (TDST) leads to the formation of three new salts, which have been characterized by elemental analyses, thermogravimetric analyses, FTIR spectroscopy, and their structures were determined by single-crystal X-ray diffraction. Structural analyses indicate that in all three compounds a proton transfer has...
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Reactivity study of a β-diketiminate titanium(III) complex with a phosphanylphosphido ligand towards chlorophosphanes. A new method of synthesis of β-diketiminate titanium(IV) complexes with versatile phosphanylphosphinidenes
PublikacjaThe reactivity of ab-diketiminate titanium(III) complex with a phosphanylphosphido ligand, [MeNacNacTi(Cl){g2-P(SiMe3)-PtBu2}] (1)(MeNacNac= [Ar]NC(Me)CHC(Me)N[Ar]; Ar = 2,6-iPr2Ph), was investigatedtowards selected chlorophosphanes, such astBu2PCl,iPr2PCl, Cy2PCl, (Cy)tBuPCl, (Me)tBuPCl, (Ph)tBuPCl, Ph2PCl, (iPr2N)tBuPCl and (Et2N)2PCl. The reactions withtBu2PCl and Ph2PCl lead mainly to theearlier described complex [MeNacNacTi(Cl){g2-P-PtBu2}]...
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Phosphanylphosphido and phosphanylphosphinidene complexes of zirconium(IV) supported by bidentate N,N ligands
PublikacjaPhosphanylphosphido complexes of zirconium, [NacNacZrCl2(η2-R2P–PSiMe3)] (R = t-Bu, i-Pr), were synthesized in the reaction of R2P–P(SiMe3)Li·nTHF (R = t-Bu, i-Pr) with a β-diketiminate complex, [NacNacZrCl3], in toluene. Elimination of Me3SiCl from [NacNacZrCl2(η2-R2P–PSiMe3)] provided the phosphanylphosphinidene complexes [NacNacZrCl(η2-R2P–P)] (R = t-Bu, i-Pr). Moreover, the reaction of [NacNacZrCl2(η2-R2P–PSiMe3)] with R2P–P(SiMe3)Li·nTHF...