Non-covalent expansion of an organic bilayer involving exo-cavity interplay of tetraphenylphosphonium with para-sulfonato-calix[4]arene

Reaction of equimolar amounts of sodium para-sulfonato-calix[4]arene, tetraphenylphosphonium chloride and ytterbium chloride in water results in the formation of a mineral clay-like structure, where the hydrophobic tetraphenylphosphonium cations interpose a bilayer arrangement based on a 2D coordination polymer of (calix[4]arene)5-/Na+/Yb3+.     

Constructing 2D porous material based on the assembly of large organic ions: p-sulfonatocalix[8]arene and tetraphenylphosphonium ions

In the presence of tetraphenylphosphonium and aquated ytterbium(III) ions, conformationally flexible p-sulfonato-calix[8]arene forms an extended structure with two dimensional porosity involving the assembly of phosphonium cations and 'molecular capsules' comprised of two calixarenes shrouding three phosphonium cations.     

Synthesis and Structure of Tetraphenylphosphonium Carboxylates

Hydrates of tetraphenylphosphonium carboxylates were synthesized by the reaction of equimolar amounts of pentaphenylphosphorus with 2-methoxybenzoic, 2-nitrobenzoic, and maleic acids in benzene. The product of the pentaphenylphosphorus reaction with tetrafluorophthalic acid (mole ratio 2: 1) is bis- (tetraphenylphosphonium) tetrafluorophthalate hydrate. According to the X-ray analysis data, crystals of tetraphenylphosphonim carboxylates are formed by tetraphenylphosphonim tetrahedral cations and single- or double-charged carboxylate anions. Structural organization of the crystals is determined by C–H···O weak hydrogen bonds formed with the participation of carboxylate groups and water molecules or manifold C–H···F interactions between cations and anions.     

Exploiting phenyl embraces and pi-stacking in the assembly of arrays of tetraphenylphosphonium p-sulfonatocalix[4]arene

Phenyl embraces involving tetraphenylphosphonium cations feature in complexes of p-sulfonatocalix[4]arene where a phenyl ring of a cation is included in the cavity of the calixarene. The overall structures are based on pseudo-polymorphic supramolecular arrays and their formation is templated or induced by lanthanide ions.     

Synthesis,Crystal Structure,Optical, Magnetic,and Thermal Properties of the New Heteroleptic Chromium Complex [Ph4P][Cr(en)(S5)2]

The new heteroleptic chromium complex [Ph₄P][Cr(en)(S₅)₂] has been synthesised under mild solvothermal conditions by the reaction of chromium trichloride, sulfur, and tetraphenylphosphoniumbromide in a solution of ethylendiamine ( en ) in water. The crystal structure consists of isolated tetraphenylphosphonium cations and [Cr(en)(S₅)₂]^– anions. The Cr³⁺ cations are in an octahedral coordination of two bidentate S₅^2– polysulfide anions and one bidentate en ligand. The N atoms of the en ligand and the terminal S atoms of the S₅^2– anions bonded to the Cr³⁺ ions are in a cis-position. The six-membered CrS₅ rings are in a chair conformation. The three dimensional arrangement of the cations and anions is achieved via intermolecular hydrogen bonds. Investigations with differential thermal analysis (DTA) combined with thermogravimetry (TG) show a stepwise decomposition. In the first step the en ligand is removed completely followed by the emission of a part of the tetraphenylphosphonium cations and the sulfur atoms in the second step. The temperature dependence of the magnetic susceptibility exhibits a Curie-Weiss behaviour with an effective magnetic moment typical for a Cr³⁺ (d³) ion and a value for the Weiss constant of 1.3(2) K. Fourier transform infrared spectroscopy (FTIR) was also performed to characterise the optical properties.     

Site specific Co(III) sarcophagine binding in multi-component phosphonium and p-sulfonatocalix[4]arene systems

Co(III) sarcophagine-type cage molecules, [Co(diCLsar)](3+) or [Co(HONOsar)](3+), form either 1 : 1 or 1 : 2 host-guest inclusion complexes with mono-phosphonium cations and sodium p-sulfonatocalix[4]arene in the solid state yielding complex I [p-sulfonatocalix[4]arene·Co(diCLsar)·2{benzyltriphenylphosphonium}], complex II [2{p-sulfonatocalix[4]arene}·Co(diCLsar)·3{tetraphenylphosphonium}] and complex III [p-sulfonatocalix[4]arene·Co(HONOsar)·tetraphenylphosphonium]. The diversity of the structural types of these multi-component systems, including the orientation of the Co(III) molecules in the cavities of the calixarenes, depends on the nature of their terminal functional groups. The secondary coordination interactions binding between the Co(III) molecules and p-sulfonatocalix[4]arene have also been investigated in water using NMR techniques.     

Poly[tetraphenylphosphonium copper(I)‐di‐μ2‐dicyanamido]

In the title compound, {(C₂₄H₂₀P)[Cu(C₂N₃)₂]}_n, the copper(I) dicyanamide anion forms a distorted three‐dimensional single diamondoid network. Templating tetraphenylphosphonium cations reside within the cavities of the polymeric anion.     

Molecular tectonics. Selective exchange of cations in porous anionic hydrogen-bonded networks built from derivatives of tetraphenylborate

Tetraphenylmethanes with multiple hydrogen-bonding sites are known to associate to form robust porous supramolecular networks. Analogous anionic networks can be built from the corresponding tetraphenylborates. Crystallization of the tetraphenylphosphonium salt of tetraphenylborate 2 produces an anionic network in which 74% of the volume is available for including cations and neutral guests. Other salts of anion 2 with diverse cations crystallize consistently to form the same network, whereas a neutral analogue of anion 2, tetraphenylmethane 1, produces an uncharged network that is far less open. Cations can be exchanged in single crystals of salts of tetraphenylborate 2 with retention of crystallinity and with selectivities similar to those observed in typical zeolites. Together, these observations provide new strategies for making ordered molecular materials by design, and they reveal that constructing such materials from charged subunits offers special advantages.     

Synthesis and Structure of Phosphorus-Containing Complexes [Ph4P]

Complexes [Ph₄P] ₂ ⁺ [Hg₄I₁₀]²⁻ (I) and [[Ph₄P] ₂ ⁺ [BiI₅(Me₂S=O)]²⁻ (II) are synthesized by the reactions of tetraphenylphosphonium Ph₄PI with mercury diiodide in acetone and with bismuth triiodide in dimethyl sulfoxide, respectively. According to X-ray diffraction analysis, structural units of these complexes are tetraphenylphosphonium cations and tetra- and mononuclear anions, respectively. The phosphorus atoms in the tetraphenylphosphonium cations have a distorted tetrahedral coordination. In the central fragment of the centrosymmetric anion [Hg₄I₁₀]²⁻, the distances between the terminal mercury atoms and iodine atoms are 3.503(2) Å. The mercury atoms in the central and terminal fragments of compound I have distorted tetrahedral and trigonal coordinations, respectively. The bismuth atom in the mononuclear octahedral anion of complex II contains a dimethyl sulfoxide molecule along with five iodine atoms in the coordination sphere. __________ Translated from Koordinatsionnaya Khimiya, Vol. 31, No. 10, 2005, pp. 791–795. Original Russian Text Copyright ? 2005 by Sharutin, Egorova, Sharutina, Dorofeeva, Molokov, Fukin.     

Pd-Catalyzed Arylation of Phosphines: Reversibility and Ligand Exchange Issues

Abstract

Our studies on the fate of the phosphine co-catalyst in the Heck arylation reaction have revealed that the quaternary tetraarylphosphonium cations which are formed from triphenylphosphine and aryl iodide under the reaction conditions undergo an aryl exchange process with the aid of the palladium catalyst Independent exchange studies as well as model Heck arylation reactions carried out in the presence of stoichiometric amounts of tetraphenylphosphonium iodide demonstrated clearly that the Pd-catalyzed aryl exchange between aryl iodide and tetraarylphosphonium cation is a facile process which can effectively compete with the Heck arylation The observed exchange process is reversible and involves triarylphosphines as discrete intermediates.     

Organic Pillared Clays

Commonly used organophilic clays are modified by alkylammonium cations which hold apart the aluminosilicate layers permanently. The cations fill the interlayer space and are contemplated as flexible pillars, resulting from the mobility of the alkyl chains. Therefore, the interlayer distance varies depending on the layer charge and on the alkyl chain length. Contrary to these cations, rigid pillaring cations guarantee a constant interlayer distance without occupying the interlayer by themselves and show special adsorption properties such as hydrophilic behavior contrary to the generally hydrophobic ones. Smectites were modified by flexible organic cations, e.g., dimethyldioctadecylammonium, and by rigid ones, e.g., tetraphenylphosphonium. Their adsorption properties are compared. Our investigations showed improved adsorption properties for rigid organic cations on smectites using 2-chlorophenol as pollutant. Best adsorption results are achieved using pillaring cations in combination with low charged smectites, especially at low pollutant concentrations. The properties of organic modified smectites are discussed by a pollution intercalation model. The intercalation process of an organic pollutant into an organic modified smectite is expressed by a two-step Born-Haber cycle process: (i) the formation of an adsorbing position by layer expansion and (ii) the occupation of the adsorbing position by the pollutant. The first step of the formation of the adsorbing position is an endothermal transition state which lowers the total intercalation energy and therefore worsens the adsorption behavior. Thus, an already expanded organophilic smectite will show improved adsorption behavior. The formed adsorbing position state on organic modified smectites is comparable to the pillared state of inorganic pillared clays. Copyright 2001 Academic Press.     

Adsorption of phenanthrene on organoclays from distilled and saline water

Isotherms of phenanthrene adsorption on different organoclay complexes were obtained using the HPLC technique to understand the adsorption behavior and to characterize the effect of sodium chloride (NaCl) on the adsorption. The adsorbed amounts of phenanthrene on montmorillonite exchanged by organic cations such as tetraheptylammonium, benzyltrimethylammonium, hexadecyltrimethylammonium, or tetraphenylphosphonium were several times higher than those obtained using montmorillonite clay without surface modification. At the same equilibrium concentration, the adsorbed amount of phenanthrene is higher on clay modified with benzyltrimethylammonium than on clay modified with hexadecyltrimethylammonium or other cations. Adsorption of phenanthrene on clay modified with benzyltrimethylammonium increased dramatically as the concentration of NaCl increased up to 150 g/l in the aqueous solution. The shape of the curves obtained can be classified as S-type. The adsorption data obtained from salinity experiments support a mathematical model that links the Langmuir constant with the salinity constant. This model may be useful to predict the equilibrium concentration of a contaminant in saline solution. FTIR studies showed strong interactions between the aromatic rings of phenanthrene and the preadsorbed benzyltrimethylammonium on clay surfaces.     

Metallboranate und Boranato-metallate. VI. Zur Reaction von Oniumboranaten mit Trimethylamin-Alan: Trimethylamin-boranato-alanat,BH4 · AlH3 · N(CH3) und Onium-alanate

Trimethylamine-alane adds to tetrabutylammonium tetrahydroborate in benzene to yield tetrabutylammonium trimethylamine-tetrahydroborato-trihydroaluminate. The BH₄ group of this novel complex hydrido-anion is bound via a single hydrogen bridge to the aluminium atom. Although there is ir-spectroscopic evidence for the formation of a similar tetraphenylphosphonium salt in the reaction of tetraphenylphosphonium tetra-hydroborate and trimethylamine-alane (employed in excess), the products are tetraphenylphosphonium tetrahydroaluminate and trimethylamine-tetrahydroborato-alane. However, tetraphenylarsonium tetrahydroborate yields triphenylarsine and (CH₃)₃N · AlH₂BH₄ under similar conditions. Tetrabutylammonium, tetraphenylphosphonium and tetraphenylarsonium tetrahydro-aluminates were prepared from the respective tetrahydroborate and LiAlH₄.     

Synthesis,Structure and Raman Data of the New Binuclear Zirconium Complex [Ph4P]2[(ZrCl4Py)2O], with a Zr‐O‐Zr Bridge

The new Zirconium(IV) coordination compound [Ph₄P]₂[(ZrCl₄Py)₂O] (Ph = phenyl, Py = pyridine) was synthesized by dissolving ZrCl₄, [Ph₄P]Cl and a stoichiometric amount of NaOH/Na mixture in pyridine or pyridine/organic solvent mixtures. The title phase was obtained as colourless crystals. The crystal structure of [Ph₄P]₂[(ZrCl₄Py)₂O] was determined. It crystallizes monoclinic, P2₁/c, Z = 4, a = 13.412(2), b = 13.461(2), c = 16.442(3) Å, β = 102.72(1)°. The structure consists of isolated tetraphenylphosphonium cations and [(ZrCl₄Py)₂O]^2? complex anions. The centrosymmetric complex anion contains a linear Zr–O–Zr bridge. Each Zr atom is coordinated by one oxygen dianion, the N atom of one pyridine ring and four chloro ligands in a distorted octahedral geometry. The Raman spectrum of [Ph₄P]₂[(ZrCl₄Py)₂O] is also reported. Most of the observed frequencies can be assigned to vibrations of the tetraphenylphosphonium cations and the pyridine rings.     

Ylide mediated polymerization of methacrylates and acrylates in the presence of tetraphenylphosphonium cation 3

Triphenylmethide tetraphenylphosphonium (TPM, TPP) or methylisobutyrate tetraphenylphosphonium (MIB, TPP) formed by ion exchange reactions of TPP chloride(TPPCl) with the TPM or MB potassium salts in THF, initiate the living polymerization of MMA producing PMMA's with narrow MW distributions (below 1.3) at ambient temperatures.     

Adsorption of tetraphenylphosphonium chloride at the mercury-water interface

Interfacial tersion measurements of mercury in contact with aqueous solutions of tetraphenylphosphonium chloride indicate the existence, at negative rational potentials, of an ordered monolayer of tetraphenylphosphonium ions, either as such or as its neutral salt. The analysis clearly illustrates the limits to the molecular information obtainable from electrical measurements.     

Synthesis and Spectroscopic Characterization of Novel Aryl-Dithiofluorophosphonate Derivatives and X-Ray Studies of [(4-CH3OC6H4)(F)P(S)S−][PH4P+]

Abstract

Potassium and tetraphenylphosphonium salts of novel aryldithiofluorophosphonic acids were synthesized. Lawesson's Reagent was allowed to react with KF in acetonitrile to yield the potassium salt of p-methoxyphenyldithiofluorophosphonic acid. Treatment of the latter with tetraphenylphosphonium chloride resulted in the formation of the tetraphenylphosphonium salt. The structures of the compounds were elucidated by FTIR, ¹H, ¹³C, ¹⁹F, and ³¹P NMR spectroscopy as well as by ESI-mass spectrometry. The molecular and crystal structure of the tetraphenylphosphonium salt, determined by single crystal X-ray diffraction, is also presented.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.     

Exchange coupling across the cyanide bridge: structural and DFT interpretation of the magnetic properties of a binuclear chromium(III) complex

The reaction of [Cr(CN)6]3- with a mixture of trans-[Cr(cyclam)(OH)2]Cl, [Cr(cyclam)(OH)Cl]Cl and [Cr(cyclam)Cl2]Cl affords the cyanide bridged dimer, trans-[HO-Cr(cyclam)-NC-Cr(CN)5]-. The tetraphenylphosphonium salt of the anion crystallizes in space group P2(1)/n and shows a bent arrangement of the Cr1-CN-Cr2 unit with the Cr1-CN bond angle at 166.9 degrees and CN-Cr2 at 160.32 degrees . The Cr2-O bond, trans to the hexacyanide fragment, is very short at 1.902 A. Two dimers are held together by two hydrogen bonds connecting the Cr2-OH group of each dimer with one of the NH groups of the cyclam ligand of an adjacent molecule, leading to an almost linear configuration. These dimers of dimers get packed parallel to each other, generating layers separated by the tetraphenylphosphonium cations. Four of the cyanide groups of the anion are engaged in H-bonds with the four water molecules present in the structure or with a NH group of the macrocycle of an adjacent molecule. From magnetic susceptibility measurements, the dimer was found to exhibit antiferromagnetic interaction between the Cr(III) centers with J=-16 cm(-1)(H=-2JS(A)S(B)). Structural and magnetic parameters have been calculated by density functional theoretical methods at the B3LYP level. The exchange coupling constant, J, calculated for the dimer at the X-ray geometry is -23.2 cm(-1) which is in excellent agreement with the experimental value.     

Synthesis and Properties of Onium Salts of Isocyanuric Acid. Crystal Structure of Tetraphenylphosphonium Isocyanurate

Previously unknown tetrabutylammonium and tetraphenylphosphonium isocyanurates were prepared, and their IR spectra were examined. The crystal structure of tetraphenylphosphonium isocyanurate was determined.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 3, 2005, pp. 417–421.Original Russian Text Copyright © 2005 by Flakina, Chekhlov, Kushch, Lyubovskaya.