Darstellung und Eigenschaften von Tris(diphenylamino)-phosphin

Preparation and Properties of Tris (diphenylamino) Phosphine The synthesis and some properties of tris(diphenylamino)phosphine are described. Displacement of the chlorine atom is readily achieved by reaction of (Ph₂N)₂PCl with Ph₂NSime₃. Thus tris(diarylamino)phosphine (Ph₂N)₃P is obtained almost in quantitativ yield. The aminolysis reaction of PCl₃ or (Ph₂N)₂PCl with Ph₂NH gives also (Ph₂N)₃P. The properties and structure of the phosphine on basis of spectroscopical and X-ray investigations are discussed.     

Effective Control of the Electron-donating Ability of Phosphines by using Phosphazenyl and Phosphoniumylidyl Substituents

Phosphoniumylidyl and phosphazenyl groups are effective substituents to increase the electron-donating ability of tertiary phosphines. However, the influence of structural variations among those substituents on the electronic properties of the phosphines is little explored. Herein, we show that protonation of the ylidic carbon atom of phosphoniumylidyl phosphines increases the Tolman electronic parameter (TEP) by ΔTEP = 16.0–18.8 cm^–1. Furthermore, phosphazenyl phosphines were synthesized with isopropyl groups (NP{iPr}₃) and tetramethylguanidino groups (NP{tmg}₃) at the phosphonium center. Determination of their TEP values reveals a remarkable low substituent parameter of χ = –18.5 cm^–1 for the NP(tmg)₃ group. In addition, we prepared the corresponding gold(I) complexes and determined their solid-state structures using single-crystal X-ray diffraction studies to analyze the steric profile of the new phosphine ligands.     

Tris(2‐pyridyl)­phosphine oxide: how C—H⃛O and C—H⃛N interactions can affect crystal packing efficiency

Tris(2‐pyridyl)­phosphine oxide, (I), C₁₅H₁₂N₃OP, is isomorphous with tris(2‐pyridyl)­phosphine. Because of a combination of C—H⋯O and C—H⋯N interactions, the crystal packing is denser in the title compound than in the related compounds tri­phenyl­phosphine oxide and tris(2‐pyridyl)­phosphine.     

Dinuclear copper complexes of pyridylphenylphosphine ligands: Characterization of a mixed-valence Cu/Cu dimer

Homo bi-copper complexes [Cu₂{PhP(2-py)₂}₂(NO₃)₃] (1) and [Cu₂{P(2-py)₃}₂Cl₂] (2), were synthesized from the reaction of Cu(NO₃)₂·3H₂O and CuCl₂·2H₂O with their corresponding 2-pyridylphosphine ligands. Compound 1 has a mixed valence Cu(I)-Cu(II) core with electron acceptor phosphine atoms and two NO₃⁻ anions coordinated in a monodentate fashion to Cu(I), giving it a distorted tetrahedral geometry. The environment of Cu(II) in 1 is composed of four nitrogen atoms from pyridyl and another NO₃⁻ anion in a square pyramidal geometry. This complex shows luminescence and a low energy absorption band at 969 nm corresponding to intermetallic electron transfer between the copper centers. Complex 2 was prepared from the treatment of copper(II) chloride with tris(2-pyridyl)phosphine, producing a binuclear copper complex which possesses a crystallographic inversion center. The copper geometry in this complex is distorted tetrahedral with coordination of one Cl⁻, two nitrogens from one bridging tris(2-pyridyl)phosphine ligand and one P atom from the other bridging tris(2-pyridyl)phosphine ligand, in a similar way observed in related complexes. The products have been characterized by spectroscopic methods and also by the single-crystal X-ray diffraction method.     

Phosphine-substituted diiron 1,2-dithiolate complexes as the models for the active site of [FeFe]-hydrogenases

Abstract

In this article, five diiron 1,2-dithiolate complexes containing phosphine ligands are reported. Treatment of complex [Fe₂(CO)₆(μ-SCH₂CH₂S)] (1) with the phosphine ligands tris(4-methylphenyl)phosphine, tris(4-methoxyphenyl)phosphine, tris(3-chlorophenyl)phosphine, tris(3-methylphenyl)phosphine, or 2-(diphenylphosphino)biphenyl in the presence of Me₃NO·2H₂O as the decarbonylating agent afforded the target products [Fe₂(CO)₅(L)(μ-SCH₂CH₂S)] [L?=?P(4-C₆H₄CH₃)₃, 2; P(4-C₆H₄OCH₃)₃, 3; P(3-C₆H₄Cl)₃, 4; P(3-C₆H₄CH₃)₃, 5; Ph₂P(2-C₆H₄Ph), 6] in 80–93% yields. Complexes 2–6 have been characterized by elemental analysis, spectroscopy, and X-ray crystallography. Additionally, the electrochemical properties were studied by cyclic voltammetry.     

Adsorption and elektrokinetic properties of the system: carboxymethylcellulose/manganese oxide/surfactant

The adsorption of carboxymethylcellulose (CMC) in the presence of the surfactants: anionic SDS, nonionic polyethylene glycol p-(1,1,3,3-tetramethylbutyl)-phenyl ether (Triton X-100) and their mixtures SDS/polyethylene glycol p-(1,1,3,3-tetramethylbutyl)-phenyl ether with different molar ratios (1:1; 1:3 and 3:1) from the electrolyte solutions (NaCl, CaCl₂) on the manganese dioxide surface (MnO₂) was studied. In every measured system the increase of CMC adsorption in the presence of surfactants was observed. This increase was the smallest in the presence of SDS, a bit larger in the presence of polyethylene glycol p-(1,1,3,3-tetramethylbutyl)-phenyl ether and the largest when the mixtures of SDS/polyethylene glycol p-(1,1,3,3-tetramethylbutyl)-phenyl ether were used. Among the measured mixtures, the mixture of SDS/polyethylene glycol p-(1,1,3,3-tetramethylbutyl)-phenyl ether with the molar ratio 1:3 caused the largest increase of CMC adsorption amount. These results are a consequence of formation of complexes between the carboxymethylcellulose macromolecules and the surfactant molecules. In order to determine the electrokinetic properties of the system the surface charge density of MnO₂ and the zeta potential measurements were conducted in the presence of the CMC macromolecules and the surfactants. The obtained data showed that the adsorption of CMC or CMC/surfactants complexes on the manganese dioxide surface strongly influences the structure of the electric double layer MnO₂/electrolyte solution.     

Boronate Covalent and Hybrid Organic Frameworks Featuring PIII and P=O Lewis Base Sites

Two covalent organic frameworks comprising Lewis basic P^III centers and Lewis acidic boron atoms were prepared by poly-condensation reactions of newly obtained tris(4-diisopropoxyborylphenyl)phosphine with 2,3,6,7,10,11-hexahydroxytriphenylene and 2,3,6,7-tetrahydroxy-9,10-dimethylanthracene. Obtained materials exhibit significant sorption of dihydrogen (100 cm³ g⁻¹ at 1 bar at 77 K), methane (20 cm³ g⁻¹ at 1 bar at 273 K) and carbon dioxide (50 cm³ g⁻¹ at 1 bar at 273 K). They were exploited as solid-state ligands for coordination of Pd⁰ centers. Alternatively, in a bottom-up approach, boronated phosphine was treated with Pd₂dba₃ and poly-condensated, yielding hybrid materials where the polymer networks are formed by means of covalent boronate linkages and coordination P−Pd bonds. In addition, the analogous materials based on phosphine oxide were synthesized. The DFT calculations on framework–guest interactions revealed that the behavior of adjacent boron and phosphorus/phosphine oxide centers is reminiscent of that found in Frustrated Lewis Pairs and may improve sorption of selected molecules.     

Tris(tert-butyl)phosphine selenide,the missing link in tris(tert-butyl)­phosphine chalcogenide structures tBu3P=X (X = O,S, Se,Te)

In tris(tert-butyl)­phosphine selenide, C₁₂H₂₇PSe, all the methyl ligands are disordered over two sites in the ratio 70/30. The mol­ecule displays crystallographic C₃ symmetry. The bond angles at the P atom are distorted tetrahedral [C—P—C 110.02 (5)° and Se=P—C 108.91 (5)°]. The P—C and P=Se bond lengths are 1.908 (1) and 2.1326 (6) Å, respectively. A comparison of the structural data of the complete series of tris(tert-butyl)­phosphine chalcogenides (^tBu₃PO, ^tBu₃PS, ^tBu₃PSe and ^tBu₃PTe) with the corresponding data of other phosphine chalcogenides substituted by smaller organic groups shows the great influence of the bulky tert-butyl ligands.     

Flame-retardant properties of epoxide and unsaturated polyester resins modified with tertiary phosphine oxides containing chlorinated phenoxy groups

The flame-retardant properties of the epoxide resin “Epoxa AP-2” and the unsaturated polyester resin “Vinalkid 550P” modified with dimethyl(2,4,6-trichlorophenoxymethyl)phosphine oxide (DMPO), methyl-bis(pentachlorophenoxymethyl)phosphine oxide (MBPO) and tris(2,4,6-trichlorophenoxymethyl)phosphine oxide are examined. It is established that all three products are effective fire-retardants for epoxide as well as for unsaturated polyester resins. The effect is notable at about 10–15% presence. The oxygen indexes, determined by the ASTM-D-2863 method, show an increase of several units in comparison with the unmodified resins. The fire-retardant action of DMPO, MBPO and TTPO is significantly enhanced by the addition of Sb₂O₃.     

Reaction of tris(hydroxymethyl)phosphine and cinnamaldehyde in methanol

Reaction of tris(hydroxymethyl)phosphine with excess cinnamaldehyde in CH₃OH or CD₃OD, followed using NMR, proceeds via several phosphorus-containing intermediates, multiple transformations of organic parts, and with the solvent H/D isotope effect on products. In both solvents, one CH₂OH group of tris(hydroxymethyl)phosphine is readily replaced by the cinnamaldehyde moiety to give the primary product, a 1,3-oxaphosphorinane derivative. Slower replacement of the second CH₂OH group leads to a mixture of aliphatic and heterocyclic phosphine intermediates in a ratio of ~4:1 in CH₃OH and ~1:1 in CD₃OD; both intermediates contain alcohol and aldehyde groups and convert rapidly into intra- and intermolecular hemiacetals. The hemiacetals of the aliphatic phosphine rearrange further into an unsymmetrical trialkylphosphine oxide, whereas the hemiacetals of the heterocyclic phosphine react with the third mole of cinnamaldehyde to replace the third CH₂OH group of tris(hydroxymethyl)phosphine. All intermediates and products are formed as mixtures of stereoisomers.     

Furfuryl-containing tertiary phosphine oxides and polymers based on some of them

The syntheses of dimethyl(furfuryloxymethyl)phosphine oxide (DPO), methylbis(furfuryloxymethyl)phosphine oxide (MPO), tris(furfuryloxymethyl)phosphine oxide (TPO), dimethyl(tetrahydrofurfuryloxymethyl)phosphine oxide (DTPO), methyl-bis(tetrahydrofurfuryloxymethyl)phosphine oxide (MTPO) and tris(tetrahydrofurfuryloxymethyl)phosphine oxide (TTPO) from dimethyl(chloromethyl)phosphine oxide, methyl-bis(chloromethyl)phosphine oxide, tris(chloromethyl)phosphine oxide and the furfuryl and tetrahydrofurfuryl sodium alkoxides via the Williamson reaction are reported. Phosphorus-containing furan polymers with reduced flammability are prepared by polymerizing MPO and TPO using p-toluenesulphonic acid as catalyst. The oxygen indexes of these polymers, as determined by ASTM D-2863, are 35.1 and 33.1% O₂, respectively; for the phosphorus-free polymer from difurfurylidene acetone, it is 23.0% O₂. It is shown that DPO can be used as an efficient fire-retardant for reducing the flammability of a polymer from difurfurylidenacetone.     

Synthesis,characterization, and electrochemistry of monophosphine‐containing diiron propane‐1,2‐dithiolate complexes related to the active site of [FeFe]‐hydrogenases

Five monophosphine‐substituted diiron propane‐1,2‐dithiolate complexes as the active site models of [FeFe]‐hydrogenases have been synthesized and characterized. Reactions of complex [Fe₂(CO)₆{μ‐SCH₂CH(CH₃)S}] ( 1 ) with a monophosphine ligand tris(4‐methylphenyl)phosphine, diphenyl‐2‐pyridylphosphine, tris(4‐chlorophenyl)phosphine, triphenylphosphine, or tris(4‐fluorophenyl)phosphine in the presence of the oxidative agent Me₃NO·2H₂O gave the monophosphine‐substituted diiron complexes [Fe₂(CO)₅(L){μ‐SCH₂CH(CH₃)S}] [L = P(4‐C₆H₄CH₃)₃, 2 ; Ph₂P(2‐C₅H₄N), 3 ; P(4‐C₆H₄Cl)₃, 4 ; PPh₃, 5 ; P(4‐C₆H₄F)₃, 6 ] in 81%–94% yields. Complexes 2 – 6 have been characterized by elemental analysis, spectroscopy, and X‐ray crystallography. In addition, electrochemical studies revealed that these complexes can catalyze the reduction of protons to H₂ in the presence of HOAc.     

Expedient one-pot organometallics-free synthesis of tris(2-pyridyl)phosphine from 2-bromopyridine and elemental phosphorus

2-Bromopyridine reacts with elemental phosphorus (red or white) in a superbasic KOH/DMSO(H₂O) suspension at 100 °C (for red phosphorus) and 75 °C (for white phosphorus) over 3 h to afford tris(2-pyridyl)phosphine in a 62% yield (from red phosphorus) and a 50% yield (from white phosphorus). Under microwave assistance, the reaction with red phosphorus takes just 20 min to produce tris(2-pyridyl)phosphine in 53% yield. A hitherto unknown complex, [Pd(PPy₃)₂Cl₂]·CH₂Cl₂, synthesized from tris(2-pyridyl)phosphine and PdCl₂, has the cis-configuration; this is unusual for bis(phosphino)palladium dichloride complexes.     

Insight into the cation–anion interaction in 1,1,3,3-tetramethylguanidinium lactate ionic liquid

In order to deepen the understanding of cation–anion interaction in ionic liquids (ILs), the structure and interionic interaction of 1,1,3,3-tetramethylguanidinium lactate ([tmg][L]) ion pair, including stable configuration, hydrogen bond, frontier molecular orbital, electron density, ion interaction energy and charge transfer, are studied by using ab initio calculations. It is found that more charge-localized character of [tmg][L], especially the C1 carbocation on [tmg]⁺, and the intermolecular –NH₂-associated hydrogen bonds can substantially increase the cation–anion interaction, the interaction energy is 65.3–109.3 kJ/mol higher than that of 1-n-butyl-3-methylimidazolium-based ILs. It is also found that the frontier molecular orbitals, i.e., the HOMO, HOMO + 1 of [L]⁻ and the LUMO, LUMO + 1 of [tmg]⁺, can effectively interact and more charges are transferred between cation and anion. Based on the above results, the physical property of ILs is discussed.     

Facile synthesis,X-ray analysis,and spectroscopic studies of di-iron propanedithiolate complexes with tris(aromatic)phosphine ligands

Three new propanedithiolate-type iron–sulfur complexes containing tris(aromatic)phosphine ligands, [{(μ-SCH₂)₂CH₂}Fe₂(CO)₅L] (L?=?P(PhOMe-p)₃, 1; P(PhMe-p)₃, 2; P(PhF-p)₃, 3), have been prepared through carbonyl substitution in the presence of Me₃NO. The new complexes 1–3 were characterized by elemental analysis, IR, ¹H, ¹³C{¹H}, and ³¹P{H} NMR spectra. The molecular structures of 1–3 were unequivocally determined by single crystal X-ray diffraction, in which the tris(aromatic)phosphine coordinated to Fe resides in an apical position of the pseudo-square-pyramidal geometry. IR spectroscopy and X-ray crystallographic analysis for 1–3 have indicated that the highly electron rich tris(aromatic)phosphine ligands (where the corresponding electron-donating abilities display the following order of P(PhOMe-p)₃?>?P(PhMe-p)₃?>?P(PhF-p)₃) result in a considerable red shift of the CO-stretching frequencies and a clear change of the Fe–Fe bond distances in 1–3.     

Rhodium carbonyl complexes of thetrans-[RhCl(CO)(PR3)2] type with pyridylphosphines

Summary Trans-[RhCl(CO)(PR₃)₂] complexes [PR₃=tris-(2-pyridyl)phosphine {P(2-pyl)₃}, phenylbis(2-pyridyl)phosphine {PPh(2-pyl)₂} or tris(3-pyridyl)phosphine {P(3-pyl)₃}] have been synthesized and examined by spectroscopic methods (i.r., u.v.-vis,³¹P{¹H} n.m.r.,¹H n.m.r.). In solution the P(2-pyl)₃ and PPh(2-pyl)₂ complexes exhibit equilibrium between the pentacoordinate state, with one of the phosphine molecules coordinated via nitrogen and phosphorus, and complexes with the phosphine coordinated only through nitrogens.     

Metal‐Ion Sensing Europium(III) Complexes with Bidentate Phosphine Oxide Ligands Containing a 2,2′‐Bipyridine Framework

Novel Eu^III complexes with bidentate phosphine oxide ligands containing a bipyridine framework, i.e., [3,3′‐bis(diphenylphosphoryl)‐2,2′‐bipyridine]tris(hexafluoroacetylacetonato)europium(III) ([Eu(hfa)₃(BIPYPO)]) and [3,3′‐bis(diphenylphosphoryl)‐6,6′‐dimethyl‐2,2′‐bipyridine]tris(hexafluoroacetylacetonato)europium(III) ([Eu(hfa)₃(Me‐BIPYPO)]), were synthesized for lanthanide‐based sensor materials having high emission quantum yields and effective chemosensing properties. The emission quantum yields of [Eu(hfa)₃(BIPYPO)] and [Eu(hfa)₃(Me‐BIPYPO)] were 71 and 73%, respectively. Metal‐ion sensing properties of the Eu^III complexes were also studied by measuring the emission spectra of Eu^III complexes in the presence of Zn^II or Cu^II ions. The metal‐ion sensing and the photophysical properties of luminescent Eu^III complexes with a bidentate phosphine oxide containing 2,2′‐bipyridine framework are demonstrated for the first time.     

Synthesis,crystal structures and magnetic properties of two iron (II) tris(pyridyl)phosphine selenides complexes

We reported the synthesis of tris(pyridyl)phosphine selenide (TppSe) and tris(4-methylpyridin-2-yl)phosphine selenide (MeTppSe), which were prepared by a simple and straightforward one-pot method with red phosphorus in a KOH/DMSO suspension, and treatment of resulted phosphines with selenium in hot toluene. These compounds were characterized by mass spectroscopy, ¹H, ¹³C and ³¹P NMR spectroscopies and the structure of MeTppSe was characterised by a single-crystal X-ray diffraction. Furthermore, The reactions of selenides with Fe(ClO₄)₂·6H₂O afforded two new iron(II) mononuclear metal complexes [Fe(TppSe)₂][ClO₄]₂·3DMF (1) and [Fe(MeTppSe)₂][ClO₄]₂·2DMF (2). Detailed structural analyses and magnetic susceptibility measurements confirm no spin transition from low-spin to the high-spin state between 2 and 300 K in two iron(II) complexes.     

Synthesis and Structural Characterization of the First Europium(III) Pyridylphosphine Complex, [Eu(N,N’,N”-2-Py3P)(NO3)3]

The first europium(iii) pyridylphosphine complex, [Eu(N,N’,N”-2-Py₃P)(NO₃)₃] was prepared by the reaction between Eu(NO₃)₃.6H₂O and tris(2-pyridyl)phosphine; its structure was characterized by single-crystal X-ray diffraction.     

Isomere Tritolylphosphine und deren Derivate. UV-Spektren und Dipolmomente

The UV spectra of tris(2-methylphenyl)phosphine (I), tris(3-methylphenyl)phosphine (II), tris(4-methylphenyl)phosphine (III), and of their phosphine oxides, phosphine sulfides, and methyl phosphonium iodides are given. The dipole moments of I–III in benzene at 20° C were also determined. I absorbs at the longest wavelength and this result may be interpreted by a broadening of the angle on phosphorus in I. This results also from the measured dipole moment, assuming a constant phosphorus ring moment and neglecting other ortho-effects.