Synthesis,characterization and reactions of 2,2,2-trichloroethoxy derivatives of chromium(III)

Tris(2,2,2-trichloroethoxy)chromium(III) tetrahydrofuran solvate, Cr(OCH₂CCl₃)₃ ·THF; Chlorobis(2,2,2-trichloroethoxy)chromium(III)tetrahydrofuran solvate, CrCl(OCH₂CCl₃)₂ ·THF and dichloro(2,2,2-trichloroethoxy) chromium(III) tetrahydrofuran solvate, CrCl₂(OCH₂CCl₃) ·THF have been prepared. These compounds react with various oxygen and nitrogen donor ligands to form adducts of 1:2 composition. 2,2,2-trichloroethoxy bridged structures have been proposed on the basis of their infrared and¹H nmr spectra. The diffuse reflectance spectral results are consistent with an octahedral geometry for chromium(III) whereas their low magnetic moment values suggest polymeric structures exhibiting antiferromagnetic coupling between chromium(III) atoms. The mass spectral data of Cr(OCH₂CCl₃)₃ ·THF and CrCl(OCH₂CCl₃)₂ ·THF support the dimeric structures for these complexes.

---

Synthese, Charakterisierung und Reaktionen von 2,2,2-Trichlorethoxyderivaten von Chrom(III)

Zusammenfassung Es wurde Tris(2,2,2-trichlorethoxy)chrom(III)-tetrahydrofuransolvat, Cr(OCH₂CCl₃)₃ ·THF, Chlorbis(2,2,2-trichlorethoxy)chrom(III)tetrahydrofuransolvat, CrCl(OCH₂CCl₃)₂ ·THF, und Dichlor(2,2,2-trichlorethoxy)chrom(III)tetrahydrofuransolvat, CrCl₂(OCH₂CCl₃ ·THF, hergestellt. Diese Verbindungen reagieren mit verschiedenen Sauerstoff- und Stickstoffdonorliganden unter Bildung von Addukten mit der Zusammensetzung 1:2. Basierend auf IR- und¹H-NMR-Daten wurden 2,2,2-trichlorethoxyüberbrückte Strukturen vorgeschlagen. Die Resultate aus Diffuse-Reflectance-Messungen sind mit einer oktaedrischen Geometrie um Cr(III) in Übereinstimmung, während die niedrigen Werte für die magnetischen Momente polymere Strukturen mit antiferromagnetischer Kopplung zwischen den Chrom(III)-Atomen nahelegen. Die massenspektroskopischen Daten für Cr(OCH₂CCl₃)₃ ·THF und CrCl(OCH₂CCl₃)₂ ·THF sprechen für eine dimere Struktur dieser Komplexe.

     

Bis(2, 2, 2-trichloroethoxy)cobalt(II) and chloro(2, 2, 2-trichloroethoxy) cobalt(II): synthesis and coordination chemistry

Summary Bis(2, 2, 2-trichloroethoxy) cobalt(II) and chloro(2, 2, 2-trichloroethoxy)cobalt(II) [Co(OCH₂CCl₃)₂·L] and [CoCl(OCH₂CCl₃)·L], derivatives (L=tetrahydrofuran, dioxan, triphenylarsine oxide, or pyridine) have been synthesised and characterized. They have tetrahedral geometry both in solution and in the solid state.     

Preparation,Characterization, and Reactions of Dinuclear Tris(2,2,2-trichloroethoxy) Iron(III), Fe(OCH2CCl3)3

The preparation, electrical conductivity, magnetic moments, infrared, reflectance, and ⁵⁷Fe Mössbauer spectra of tris(2,2,2-trichloroethoxy) iron(III) and its adducts with some oxygen and nitrogen donor ligands are reported. Cryoscopic data of the parent compound and its complex with ethylacetate suggest these compounds to be dimeric in nitrobenzene and benzene respectively. All the compounds are covalent with Fe^III having distorted octahedral arrangement which is achieved through alkoxy bridging. The magnetic moments are lesser than those required for the spin only value indicating antiferromagnetic interactions in Fe^III atoms. The Mössbauer spectra are explained in terms of two Fe^III high spin sites corresponding to trans- and cis-positions in the structure.     

Tris(2,2,2-trichloroethoxy)iron(III) complexes

Summary The preparation, magnetic moments, i.r., reflectance and⁵⁷Fe Mössbauer spectra of adducts of tris(2,2,2-trichloroethoxy)iron (III) complexes are reported. An alkoxybridged structure is supported by i.r. spectra.⁵⁷Fe Mössbauer spectra are explained in terms of two inequivalent sites in highspin iron(III) octahedral symmetry.Abbreviations Pic-O -picolineN-oxide - Ur urea - DMU N,N-dimethylurea - Suc succinimide - Diox dioxan - Bipy 2,2-bipyridine - Phen 1,10-phenanthroline     

4-substituted but-2-enylpalladium(II) complexes

The chloro bridges in di-μ-chloro-4-methoxy- and di-μ-chloro-4-acetoxy-2-methyl-but-2-enylchloropalladium are split by Group V donor ligands Ph₃E (where E = P, As and Sb) to give [(η)³-H₂CC(CH₃)CHCH₂X) PdCl · EPh₃], (where X = OCH₃, OCOCH₃). These complexes are readily decomposed by dilute ethanolic hydrogen chloride yielding [Ph₃E · PdCl]₂ and isoprene. The structures of the compounds are discussed in the light of their ¹H NMR spectra.     

An Unusual Mixed‐Anionic Iodine‐Rich Polyiodide: [Rb(crypt‐2,2,2)]4(I5)2(I8)

Black crystals of [Rb(crypt‐2,2,2)]₄(I₅)₂(I₈) were obtained from a dichloromethane/ethanol solution of RbI, I₂ and Kryptofix‐2,2,2®. The crystal structure (monoclinic, P2₁/c (no. 14), a = 1250.1(1), b = 2555.2(2), c = 2313.4(3) pm, β = 121.45(1)°, V = 6309.9(11)·10⁶ pm³, Z = 2) consists of [Rb(crypt‐2,2,2)]⁺ cations leaving three‐dimensional channels for the V‐shaped (I₅)^? and Z‐shaped (I₈)^2? anions which are isolated from each other.     

Ni(II) complexes with 8-aminoquinoline derivatives

Some Ni(II) complexes with 5,7-dicloro-8-aminoquinoline (dcaq), 5,7-dibromo-8-aminoquinoline(dbaq) and 5,7-diiodo-8-aminoquinoline(diaq) are described. The compounds are of stoichiometry NiL₂X₂(L= dcaq, dbaq, diaq; X= NO^?₃ and L= dbaq; X= Cl^?, Br^?, I^?, NCS^?) and NiLX₂·H₂O(L= dcaq, diaq; X= Cl^?). The electronic spectra and magnetic susceptibility data at room temperature, are consistent with octahedral geometry for the Ni(II) in each compound. I.r. spectra show the presence of ionic and bridging nitrate groups in the compounds NiL₂(NO₃)₂(L= dcaq, dbaq, diaq) and we assign them polymeric structures. Polymeric structures with bridging chloride are proposed for the compounds NiLCl₂·H₂O(L= dcaq, diaq) and monomeric octahedral structures for NiL₂X₂(L= dbaq; X= Cl, Br, I, NCS).     

Reaktionsprodukte aus Chlormethoxiphosphinen und Antimon(V)-chlorid. Schwingungsspektren der 1:1 Addukte aus Methoxiphosphorylverbindungen und Antimon(V)-chlorid

Reaction Products of Chloromethoxiphosphines and Antimony (V) Chloride. Vibrational Spectra of the 1:1-adducts of Methoxiphosphoryl Compounds and Antimony (V) Chloride Chloromethoxiphosphines react with antimony(V) chloride in a redox process to yield the chloromethoxiphospllonium hexachloroantimonates(V) (CH₃O)₃PCl₂⁺SbCl₆^? (II) and CH₃OPCl₃⁺SbCl₆^? (III). II, III, (CH₃O)₃PCl⁺SbCl₆^?(1) and (CH₃O)₄P⁺SbCl₆^? eliminate easily methyl chloride and give the addition compounds OP(OCH₃)₃·SbCl₅(IV), OPCl(OCH₃)₂ · SbCl₅ (V), OPCl₂(OCH₃)·SbCl₅ (VI) and OPCl₃·SbCl₅ (VII). The vibrational spectra of IV, V nnd VI are discussed.     

Novel tetranuclear cubane-like Co(II) complexes involving chelate phosphoramide ligands

Interaction of cobalt(II) ions and sodium carbacylamidophosphates Na(L) (HL=PhC(O)NHP(O)(NR₂)₂; where NR₂ are morpholyl, HL¹; NMe₂, HL²; NEt₂, HL³) in methanol solution afforded polynuclear alkoxo complexes [Co₄{L¹}₃(OCH₃)₄(OH)(H₂O)₅·3H₂O] 1 and [Co₄{L}₄(OCH₃)₄(CH₃OH)₄] (L=L² 2, L³ 3). Data of spectral and TGA studies are presented. Coordination compounds 1 and 3 have been characterized by means of X-ray diffraction. Both the structures consist of tetranuclear cubane alkoxo clusters with methoxide ions bridging three metal centers (CoO 2.068(3)–2.093(4) Å) and phosphorylic ligands coordinated in a bidentatechelate fashion via the carbonyl oxygen atoms (CoO 1: 2.050(2); 3: 2.031(4) Å) and the phosphoryl groups (2.093(2) and 2.106(4) Å). Isolation of these cubane alkoxo complexes is an important proof for close resemblance in behavior of carbacylamidophosphate systems and β-diketonates towards transition metal ions.     

New fluorous ponytailed 4‐[(2,2,2‐trifluoroethoxy)methyl]pyridinium halide salts

It is possible that fluorous compounds could be utilized as directing forces in crystal engineering for applications in materials chemistry or catalysis. Although numerous fluorous compounds have been used for various applications, their structures in the solid state remains a lively matter for debate. The reaction of 4‐[(2,2,2‐trifluoroethoxy)methyl]pyridine with HX (X = I or Cl) yielded new fluorous ponytailed pyridinium halide salts, namely 4‐[(2,2,2‐trifluoroethoxy)methyl]pyridinium iodide, C₈H₉F₃NO⁺·I⁻, (1), and 4‐[(2,2,2‐trifluoroethoxy)methyl]pyridinium chloride, C₈H₉F₃NO⁺·Cl⁻, (2), which were characterized by IR spectroscopy, multinuclei (¹H, ¹³C and ¹⁹F) NMR spectroscopy and single‐crystal X‐ray diffraction. Structure analysis showed that there are two types of hydrogen bonds, namely N—H…X and C—H…X. The iodide anion in salt (1) is hydrogen bonded to three 4‐[(2,2,2‐trifluoroethoxy)methyl]pyridinium cations in the crystal packing, while the chloride ion in salt (2) is involved in six hydrogen bonds to five 4‐[(2,2,2‐trifluoroethoxy)methyl]pyridinium cations, which is attributed to the smaller size and reduced polarizability of the chloride ion compared to the iodide ion. In the IR spectra, the pyridinium N—H stretching band for salt (1) exhibited a blue shift compared with that of salt (2).     

Synthesis,structure, spectroscopic,and DNA binding properties of Co(III) and Ni(II) complexes with ((E)-2-(amino((pyridin-2-ylmethylene)amino)methylene)maleonitrile)

Two new complexes, [Co(L)₂]Cl·(MeOH)₂ (1) and [Ni(L)₂]₄·EtOH (2) (L?=?(E)-2-(amino((pyridin-2-ylmethylene)amino)methylene)maleonitrile), were synthesized and characterized by X-ray crystallography, IR, UV, and fluorescence spectroscopy. According to X-ray crystallographic studies, each metal was six-coordinate with six nitrogens from two ligands. Both complexes form two-dimensional supramolecular networks via hydrogen bonding and π–π interactions. Ultraviolet and visible spectra showed that absorptions arise from π–π ^?, MLCT, and d–d electron transitions. Fluorescence spectroscopy revealed moderate intercalative binding of these two complexes with EB–DNA, with apparent binding constant (K _app) values of 9.14?×?10⁵ and 3.20?×?10^5?M^?1 for Co(III) and Ni(II) complexes, respectively. UV–visible absorption spectra showed that the absorption of DNA at 260?nm was quenched for 2 but quenched then improved for 1 with addition of complexes, tentatively attributed to the effect of the combined intercalative binding and electrostatic interaction for 1.     

Synthesis,spectroscopic and structural studies of 2,2,2-trifluoroethyl phosphorodiamidate complexes with tin(IV) chloride

The two octahedral complexes SnCl₄ · 2(O)P(NR₂)₂OCH₂CF₃ (R = Me (1) or Et (2)) have been prepared from SnCl₄ and the ligands (R₂N)₂P(O)OCH₂CF₃ in chloroform solution. Both adducts have been characterised by (³¹P and ¹¹⁹Sn) NMR, IR spectroscopy and elemental analysis. The NMR data show that the complexes exist as mixtures of cis and trans isomers in solution with the latter isomer being the predominant species. The structure of 1 has been determined by X-ray crystallography. Accordingly, the structure is centrosymmetric and the two ligands are bound trans to each other in the octahedral tin complex. DFT/B3LYP calculations show that trans configuration does indeed lead to the lowest energy species. Comparison of the structural, NMR and theoretical data of both complexes with those related to SnCl₄ · 2L (L = (Me₂N)₃P(O) and (Me₂N)₂P(O)F) further supports the important effects of the nature of the substituents in the ligand on the stereochemistry of the complex formed.     

Synthesis of 1-(N-perfluoroalkanesulfonylamino)-2,2,2-(trichloroethyl)dialkylphosphonates and phosphonic Acids

A series of 1-(perfluoroalkanesulfonylamino)-2,2,2-(trichloroethyl)dialkylphosphonates R_fSO₂NHCH-(CCl₃)P(O)(OR)₂ has been synthesized in good yields by addition of dialkyl phosphite to N-perfluoroalkanesulfonyltrichloroaldimines R_fSO₂N=CHCCl₃ that were prepared by treatment of N,N-dichloroperfluoroalkanesulfonylamines with trichloroethylene. Acidic hydrolysis of the phosphonates gave the corresponding phosphonic acids. © 1997 John Wiley & Sons, Inc.     

Synthesis,structure, and properties of a pentanuclear cobalt(III) coordination cluster

The synthesis, X-ray structure and properties of a pentanuclear cobalt(III) coordination cluster [{L(O₂CCH₃)Co₂O(OCH₃)₂}₂Co](ClO₄)₃ (1) (L^? = 2,6-bis((3-aminopropylimino)methyl)-4-methylphenolate) are described. The dinucleating L^? is coordinated with two cobalt(III) centers to form the {L(O₂CCH₃)Co₂O(OCH₃)₂} unit, where each metal center is in a distorted octahedral N₂O₄ environment. The oxo and the methoxo ligands of these two dinuclear units assemble a distorted octahedral O₆ coordination sphere around the central cobalt(III). Elemental analysis and spectroscopic (IR, NMR, UV–vis, and HRMS) features are consistent with the pentanuclear structure of the complex. The diamagnetic complex is a 1?:?3 electrolyte in solution. It is redox-active and displays a metal-centered reduction at E_1/2 = ?0.04 V (vs. Ag/AgCl).     

Synthesis,structures and magnetic properties of nickel bis (dithiolene) complexes with [Fe(qsal)2]+

Two new compounds containing the possible Fe(III) spin-crossover cation, [Fe(qsal)₂]⁺ (qsalH = N-(8-quinolyl)salicylaldimine), and nickel bis(dithiolene) anions have been synthesized. Both are 1 : 1 salts [Fe(qsal)₂][Ni(dddt)₂] · CH₃CN · CH₃OH (1) and [Fe(qsal)₂][Ni(pddt)₂] (2) (dddt = 5,6-dihydro-1,4-dithiin-2,3-dithiolate; pddt = 6,7-dihydro-5H-1,4-dithiepin-2,3-dithiolate). They have been characterized by X-ray crystal structure determination, elemental analysis, UV-Vis spectra and magnetic susceptibility measurements. The UV–Vis spectra are dominated by [Ni(L)₂]^? (1, L = dddt; 2, L = pddt). Magnetic studies show antiferromagnetic interaction in 1 from intermolecular S···S contacts and π–π stacking interactions, while the antiferromagnetic interaction in 2 is very weak.     

Crystal structures and magnetic interactions in nickel(II) dibridged complexes formed by both phenolate oxygen-azide,or methanlate groups

Abstract  

Tridentate Schiff base ligands L¹ and L², derived from the condensation of 2-hydroxy-3-methoxybenzaldehyde (L) with 2-aminoethanol or 2-aminobutan-1-ol, react with nickel chloride, azide, or thiocyanate to give rise to two dinuclear complexes of formulas [Ni₂(L)(L¹)₂N₃]·H₂O (1), [Ni₂(L²)₃(μ_1,1-N₃)]·2H₂O (2), and one tretranuclear complex [Ni₂(L²)₂(NCS)]₂(C₂H₅OH)₂ (3), where L¹ = HOCH₂CH(C₂H₅)NCHC₆H₃(O⁻)(OCH₃) and L² = HO(CH₂)₂NCHC₆H₃(O⁻)(OCH₃). We have characterized these complexes by analytical, crystal structures, and variable temperature magnetic susceptibility measurements. The magnetic properties of the complexes are studied by magnetic susceptibility (χ_M) vs. temperature measurements. The χ_M T vs. T plots reveal that compounds 1, 2 and 3 are ferromagnetically coupled.     

Komplexbildung des tert-Butyliminovanadium(V)-trichlorids mit O-Donor-Liganden

Coordination Compounds of tert-Butyliminovanadium(V) Trichloride with O-Donor-Ligands The reaction of tert-butyliminovanadium(V)trichloride ( 1 ) with cyclic and acyclic ethers, ethylene carbonate and thietane has been studied. The 1:1-complexes have a different stability; reversible and irreversible cleavage of ether in the coordination sphere of the vanadium atom rearranging in ω-chloroalkanolato ligands are observed. The reaction of 1 with 2-chloroethanol, 3-chloropropanol and 5-chloropentanol yields the complexes ^tC₄H₉N = V(OR)Cl₂ (R = CH₂CH₂CH₂CH₂CH₂Cl) and [^tC₄H₉N = V(OR)Cl₂ · ROH]; in the presence of triethylamine the disubstituted compounds ^tC₄H₉N = V(OR)₂Cl are formed. The ⁵¹V NMR spectra are discussed. The crystal structure of [^tC₄H₉N = VCl₃ · DME] ( 12 ) and [^tC₄H₉N = V(OCH₂CH₂Cl)Cl₂ · HOCH₂CH₂Cl] ( 13 ) has been determined. The vanadium atoms in 13 have a distorted octahedral coordination and are linked by the oxygen atoms of the 2-chloroethanolato ligands forming a binuclear complex. In solution molecular weight measurement and ⁵¹V NMR data indicate the equilibrium between a mononuclear complex 13 and its isomer [^tC₄H₉N = V(OCH₂CH₂Cl)₂Cl · HCl].     

Synthesen,spektroskopische Eigenschaften und Kristallstrukturen zweikerniger homo- und heteroleptischer μ-Carbido-Komplexe von Eisen(IV) mit Phthalocyaninat- und Tetraphenylporphyrinat-Liganden

Syntheses, Spectroscopical Properties, and Crystal Structures of Binuclear Homo- and Heteroleptic μ-Carbido Complexes of Iron(IV) with Phthalocyaninate and Tetraphenylporphyrinate ligands μ-Carbidophthalocyaninato(2–)iron(IV)tetraphenylporphyrinato(2–)iron(IV) ( 2 ) and μ-carbido-bis(tetraphenylporphyrinato(2–)iron(IV)) ( 1 ) are synthesized by the reaction of phthalocyaninato(2–)ferrate(I) with dichlorcarbenetetraphenylporphyrinato(2–)iron(II). 1 and 2 as well as μ-carbido-bis(phthalocyaninato(2–)iron(IV)) ( 3 ) are soluble in tetrahydrofuran, but only 2 and 3 form solvent adducts 2 a and 3 a by coordination of thf to each of the iron atoms in trans position to the bridging C atom. The crystal structures of the solvates 1 · thf, 2 a · thf and 3 a · thf, crystallizing from the thf solutions, are determined: 1 · thf, orthorhombic, Fddd, a = 21.966(3) Å, b = 22.300(1) Å, c = 31.220(3) Å, Z = 8; 2 a · thf, orthorhombic, P22₁2₁, a = 14.487(3) Å, b = 20.753(5) Å, c = 25.803(7) Å, Z = 4; 3 a · thf, orthorhombic, P2₁2₁2₁, a = 12.642(1) Å, b = 22.361(7) Å, c = 23.629(3) Å, Z = 4. In all three double-decker complexes both ”︁tetrapyrrol”︁”︁ ligands are held together by a linear Fe–C–Fe bridge in a staggered ( 1 · thf, 3 a · thf) or ecliptic conformation ( 2 a · thf). The Fe–C distances vary between 1.71 and 1.64 Å (average: 1.68 Å). In 2 a · thf and 3 a · thf the iron atoms are nearly in the centre (Ct) of the (N_p)₄ planes (d(Fe–Ct) ∼ 0.1 Å), but in 1 · thf these atoms are directed by 0.27 Å towards the bridging C atom. The macrocyclic ligands of 1 · thf are severely concavely, those of 2 a · thf and 3 a · thf slightly distorted. The electronic absorption spectra and vibrational spectra are discussed.     

Fast atom bombardment mass spectrometry of neutral methanide and ionic carbene platinum(II) derivatives

The fast atom bombardment mass spectra of a series of neutral methanide and ionic carbene platinum(II) complexes of formula dPePtL₂ and [dPePt(LH)₂](BF₄)₂ (dPe = (C₆H₅)₂PCH₂CH₂P(C₆H₅)₂; L = ? C(OCH₃)-NCH₃, ? C(OCH₃) ? NC₆H₁₁, ? C(OCH₃) ? NC₆H₄p ? CH₃), respectively are reported. Glycerol, 3-mercapto-1,2-propanediol, bis (2-hydroxyethyl)sulphide, 3-nitrobenzyl alcohol, and 2,4-di-tert-pentylphenol have been used as matrices. Neutral and ionic derivatives containing the same ligand behave similarly and give the same quasi-molecular [dPePtL(L + H)]⁺ ion by different primary processes. Stepwise breakdown of the ligands L with retention or further loss of atoms or molecules of hydrogen is observed for all these complexes, followed by ejection of radicals from the dPe ligand. Elimination of CH₃OH from [dPePtL(L + H)]⁺ also occurs. The highest ionic yields of both neutral methanide and ionic carbene complexes are observed in 3-mercapto-1,2-propanediol, in bis(2-hydroxyethyl)sulphide, and in 3-nitrobenzyl alcohol with respect to glycerol. The [dPePt(LH)₂]²⁺ doubly charged ions are present in the spectra obtained with 3-nitrobenzyl alcohol and are rather strong when L is ? C(OCH₃) ? NCH₃ and ? C(OCH₃) ? NC₆H₄p ? CH₃. Substitution of ligands L with a molecule or with a fragment of a sulphur containing matrix takes place very seldom with this series of complexes.     

Synthesis and characterization of manganese and rhenium tricarbonyl complexes with (O,O,O)-donor ligands

Complexes of the type [(C₅H₅)Co{P(O)R₂}₃]^?, R = OCH₃, OC₂H₅, react as tridentate oxygen ligands L^? with [MBr(CO)₅], M = Mn, Re, in hexane or tetrahydrofuran to give the tricarbonyl derivatives [LM(CO)₃]. The slightly volatile yellow crystalline compounds have been characterized by elemental analysis, ¹H NMR, IR and mass spectra. The low CO stretching frequencies indicate that the ligands L^? are good π-donor ligands.