Phenylphosphinic Acid Research Articles

Preparation, degradation of polyaniline doped with organic phosphorus acids and corrosion essays of polyaniline–acrylic blends

Preparation and characterization of polyaniline (PANI) doped with anions containing phosphorus was investigated with the help of various technique. The chemical polymerization of aniline was carried out in acid media containing different anions of organic phosphorus acid with the use of ammonium peroxidisulfate as oxidant agent. The highest yield was observed in the case of styrilphosphonic acid. The conductivity increased in the following order: phenylphosphinic acid < 2chloroethylphosphonic acid < styrilphosphonic acid. The solubility tests carried out in DMF, DMSO and NMP showed that the presence of voluminous anions improves the solubility of doped PANI. The synthesized PANI was characterized by density, intrinsic viscosity, solubility, FTIR, UV–vis, NMR, conductivity and TGA measurements. The hardness, elasticity, resistance and protective behavior of acrylic films were determined. The acrylic dispersion based on PANI doped with anions containing phosphorus provides improved corrosion protection of carbon steel.

Brønsted Acid-Catalyzed Imine Amidation

A new method for the Brønsted acid-catalyzed addition of amide nucleophiles to imines to produce protected aminal products is described. Simple Brønsted acids (phenyl phosphinic acid and trifluoromethanesulfonimide) were shown to be excellent catalysts, providing high yields of the aminal product. A catalytic asymmetric imine amidation using sulfonamides as nucleophiles was successful when a hindered biaryl phosphoric acid catalyst derived from 2,2'-diphenyl-[3,3'-biphenanthrene]-4,4'-diol (VAPOL) was used. Excellent yields and enantioselectivities were found in these additions (up to 99% ee).

Some triple resonance experiments in solid-state CP MAS NMR: 51V/29Si, 31P/13C, and 29Si/13C

Abstract It is shown that the phenylphosphinic acid C 6 H 5 PH(O)(OH) and the octavinylsilsesquioxane [SiO 1.5 (C 2 H 3 )] 8 act as good candidates for the set-up of the Hartmann–Hahn condition under MAS condition for 31 P→ 13 C and 29 Si→ 13 C CP transfer, respectively. The study of the polyoxometalate derivative [AsW 9 O 33 ( t BuSiO) 3 (VO)]( n Bu 4 N) 3 allowed us to clearly demonstrate the effect of { 51 V} decoupling during 29 Si acquisition for this type of compounds. These examples open new possibilities for the detailed study of inorganic compounds and hybrid materials, by triple resonance solid-state NMR experiments. To cite this article: C. Bonhomme et al., C. R. Chimie 9 (2006) .

In(III) and Ga(III) sorption by polymeric resins with substituted phenylphosphinic acid ligands

The ion-exchange/complexing properties of the resins containing various substituted phenylphosphinic acid ligands towards indium and gallium cations were investigated. Uptake of the above-mentioned cations was done on the resins in acid and ester forms, at different concentration of acid and in the presence of Zn(II) as a competing ion. It was found that resins in an ester form, able only to coordinate metal cations, had very weak affinity towards indium and gallium in the entire range of sulfuric acid concentration, whereas resins in which phosphinic functionality or both phosphinic and carboxylic functionalities were in acid form displayed high affinity towards In(III) and Ga(III). In the latter case, the logarithms of a distribution coefficient were as high as 3.5–4.0 towards Ga(III) and 4.0–6.0 towards In(III) from a 0.1–0.01 M sulfuric acid solutions. The resin may be regenerated using 3 M HCl solutions.

Structure and Magnetism of a New Hydrogen-Bonded Layered Cobalt(II) Network, Constructed by the Unprecedented Carboxylate−Phosphinate Ligand [O2(C6H5)PCH2CO2]2-

By hydrothermal reaction of CoCl2 x 6H2O with K2pcc (H2pcc = phenyl(carboxymethyl) phosphinic acid) at 423 K, a novel hybrid material of formula [Co2(pcc)2 (H2O)2] x H2O has been obtained. The compound, which is the first pcc/metal complex reported, exhibits a polymeric arrangement, where cobalt metal ions, linked together by bridging carboxylate and phosphinate oxygens, form infinite chains of edge-shared CoO6 octahedra. The cobalt chains are in turn linked together through important hydrogen-bonding interactions, which create an infinite 2D architecture. The two crystallographically independent cobalt centers, both displaying distorted octahedral coordination, present different environments as one is surrounded by six ligand oxygens and the other by four ligand oxygens and by two water oxygens. Careful magnetic studies performed by a home-built alternating current susceptometer reveal that the system undergoes an antiferromagnetic transition below 2.0 K leading to a canted structure. Field-dependent studies further indicate the occurrence of a metamagnetic transition at a critical field of 650 +/- 50 G.

New insights into the degradation mechanism of poly (vinyl chloride), Part (III): Implementation of new costabilizers—Towards heavy metal free systems (HMFS)

AbstractTo replace zinc in PVC stabilized formulations and generate a Heavy Metal Free System (HMFS), different costabilizers (i.e., 6‐amino‐1,3 dimethyluracil (Uracil), sodium tetraborate (Borax), sodium phenyl phosphinate (SPP), and NPPD (N‐phenyl‐3‐acetylpyrrolidin‐2,4‐dione), and their combinations) were tested. HCl evolution showed the outstanding performance of SPP, which was overshadowed by its poor color stability. To optimize the levels of costabilizers in the formulation, experimental design was applied to two different formulations. For a formulation containing Uracil + SPP + NPPD, the induction time (Ti) could reach up to 50 min. Moreover, an induction time of more than 80 min could be obtained with the combination of the costabilizers Borax + SPP + NPPD. The dynamic stability in terms of color measurements showed that excellent color control was achieved by the addition of 2phr of Borax into the formulation, with even better results than the mixture of the three costabilizers at their highest levels (Borax + SPP + NPPD). For a formulation containing Uracil + SPP + NPPD, the best results were again obtained by the combination of the highest levels of the three costabilizers. The mechanistic action of SPP with a model compound (4C2H) was studied by 1H and 31P‐FTnmr. The reaction was obscured by the fact that SPP underwent hydrolysis in aqueous conditions. However, the color measurements showed that because the initial color was poor, it is unlikely that SPP is acting as a peroxide decomposer in the conventional sense. In addition, the great extension in the Ti means that SPP must be inhibiting chain propagation and it may do this by stabilizing the carbocation generated during the dehydrochlorination process, along with its acid scavenging activity. Thus, when the costabilizer is totally consumed, the rate of free HCl evolution is very high, as the results confirm. The fact that phenyl phosphinic acid (PPA), the acid form, did not stabilize PVC seems to be in agreement with the above reasoning. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 122–143, 2005

Chemical polymerization of aniline in phenylphosphinic acid

The chemical polymerization of aniline was performed in phenylphosphinic acid (APP) medium using ammonium peroxidisulfate as the oxidizing agent, at 0 ?C and 25 ?C. The yield of polyaniline (PANI) was about 60?69 %. The polymerization process required an induction time 8?10 times greater than in other acids (hydrochloric, sulfuric). The average density of the obtained polymer was 1.395 g cm-3 for PANI-salt and 1.203 g cm-3 for PANI-base. The acid capacity of PANI depends on the synthesis parameters and the maximum value was 15.02 meq/g polymer. The inherent viscosity of PANI was 0.662 dl/g at aniline/oxidant molar ratios &gt;2 and 0 ?C. The oxidation state was a function of the synthesis parameters and lay between 0.553?0.625, as determined from UV-VIS and titration with TiCl3 data. The PANI samples were characterized by measurements of their density, inherent viscosity conductivity, acid capacity, FTIR and UV-VIS spectrum, and thermogravimetric data.

Extraction of Rare‐Earth Elements from Nitric Acid Solutions by Selected Bifunctional Acidic Organophosphorus Compounds

The extraction of microquantities of La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and Y from HNO3 solutions by bifunctional acidic organophosphorus compounds R2P(O)CH2P(O)Ph(OH), R=Ph (I), R=Oct (II), R=p‐Tol (III), R=p‐CH3OC6H4 (IV), and Ph2P(O)CH2P(O)(OBu)(OH) (V) in organic diluents has been studied. The effect of HNO3 concentration in the aqueous phase and that of the extractant concentration in the organic phase on the extraction of metal ions is considered. The stoichiometry of the extracted complexes has been determined. The replacement of phenyl radicals in the Ph2P(O)CH2 fragment of (diphenylphosphinylmethyl)phenylphosphinic acid (I) by p‐tolyl ones has been found to increase rare‐earth ion extraction. The introduction of p‐methoxy‐phenyl or octyl substituents instead of phenyl ones at the same part of molecule I, facilitates the extraction of Eu–Lu and Y or Tb–Lu and Y, respectively. However, the extraction of other lanthanides from 3 M HNO3 solutions decreases when p‐methoxy‐phenyl or octyl‐substituted compounds in toluene are used as extractants. The replacement of phenyl radical in the P(O)OH fragment of compound I by a butoxy‐group brings about a decrease in rare‐earth elements (REE) extraction. The effect of octyl radicals substitution by phenyl ones in compound II on the extraction of lanthanide ions decreases as the atomic number of REE increases. The extraction efficiency of octyl‐substituted compound II has been observed to be higher than that of phenyl‐substituted compound I when HNO3 concentration in the aqueous phase decreased or when diluents with a small Schmidt's diluent parameter (DP) were used.

A Simple Synthesis of Pyridine Aminophosphinic Acids (V) and Pyridine Aminophosphine Oxides (VIII). The Unusual Cleavage of Pyridylmethyl‐(N‐benzylamino)‐phenylphosphinic Acids and Phosphine Oxides in Acidic Solutions.

A Simple Synthesis of Pyridine Aminophosphinic Acids (V) and Pyridine Aminophosphine Oxides (VIII). The Unusual Cleavage of Pyridylmethyl‐(N‐benzylamino)‐phenylphosphinic Acids and Phosphine Oxides in Acidic Solutions.

A Simple Synthesis of Pyridine Aminophosphinic Acids and Pyridine Aminophosphine Oxides. The Unusual Cleavage of Pyridylmethyl-( N -benzylamino)-phenylphosphinic Acids and Phosphine Oxides in Acidic Solutions

Pyridine aminophosphinic acids were synthesized in reaction of N-(benzyl)-pyridylmethylimines with ethyl phenylphosphinate, in the presence of bromotrimethylsilane. Pyridine aminophosphine oxides were obtained in excellent yields by treatment of the corresponding imines with diphenylphosphine oxide. Among these compounds, the 2-pyridyl and 4-pyridyl derivatives were subject to a simple cleavage in aqueous mineral acid solutions. Products of the cleavages were N-(pyridylmethyl)benzylamines and phenylphosphonic (or diphenylphosphinic) acid, respectively.

Extraction of Am(III) and Lanthanides from Nitric Acid Solutions with Polyfunctional Organophosphorus Acids

Extraction of microamounts of Am, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu nitrates from aqueous HNO3 with solutions of (diphenylphosphinylmethyl)phenylphosphinic, (di-p-tolylphosphinylmethyl)phenylphosphinic, (di-p-anisylphosphinylmethyl)phenylphosphinic, and (dioctylphosphinylmethyl)phenylphosphinic acids and of butyl hydrogen (diphenylphosphinylmethyl)phosphonate in toluene was studied. The metal : extractant ratio in the extractable species was determined.

Hewitt Reaction Revisited.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Four Week Feeding Toxicity Study with Phenylphosphinic Acid in Rats

Phenylphosphinic acid was fed in graded concentrations of either 0 (control), 100, 1,000, or 10,000 ppm to rats for 28 days. These concentrations provided average daily doses of 8, 76, and 779 mg/kg (males) and 9, 83, and 859 mg/kg (females). No signs of adverse response were detected at any concentration up to the highest levels tested, 10,000 ppm or 779 (male) or 859 (female) mg/kg. Parameters measured were clinical signs, growth, neurobehavior, ophthalmology, and clinical and anatomical pathology. Phenylphosphinic acid is very low in toxicity following 31 days of feeding to the rat.

Conversions of 2-Phenyl-1,3,2-dioxaphospholane Under the Action of Hydrogen Chloride

The reaction of 2-phenyl-1,3,2-dioxaphospholane with HCl gives a mixture of phenylphosphinic acid, bis(2-chloroethyl) phenylphosphonate, and phenylphosphine; therewith, intermediate oligomeric phosphonites, hydrophosphoryl compounds, and phosphoranes were detected. Thermal treatment of the reaction mixture results in formation of ethylene phenylphosphonate and (2-chloroethyl)phenylphosphinate.

Hewitt reaction revisited

A range of alkyl phenylphosphonites are prepared from the reaction of phenylphosphinic acid with the corresponding alkyl chloroformates. A mechanism for this reaction is proposed.

METAL EXTRACTION FROM NITRIC ACID SOLUTIONS BY (DIPHENYL-PHOSPHINYLMETHYL) PHENYLPHOSPHINIC ACID

ABSTRACT The extraction of microquantities of Ca, Sr, Ba, Sc, Mn, Co, Cu, Zn, Ga, Cd, In, Pb, Bi, Zr, Hf, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Th, and U from HNO3 solutions by (diphenylphosphinylmethyl)phenylphosphinic acid in organic diluents has been studied. The effect of HNO3 concentration in the aqueous phase and that of the extractant in the organic phase on the metal extraction are considered. (Diphenylphosphinylmethyl)phenylphosphinic acid possesses an extraordinary affinity for actinides and rare-earth elements. The extractive efficiency and selectivity of this compound toward rare-earth metal ions are compared with those of some multifunctional acidic and neutral organophosphorus extractants.

Extraction of Am(III) and Rare-Earth Elements from Nitric Acid Solutions with (Diphenylphosphinylmethyl)phenylphosphinic Acid

Extraction of microamounts of Am, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu nitrates from aqueous HNO3 with solutions of (diphenylphosphinylmethyl)phenylphosphinic acid in dichloroethane was studied. The stoichiometry of the extractable complexes was determined. Synergistic enhancement of the extraction of rare-earth elements in the presence of tetraphenylmethylenediphosphine dioxide was revealed.

Synthesis of functionalized phenylphosphinic acid resins through Michael reaction: Part II. Resins with multidentate ligands

Functionalized resins, containing substituted phenylphosphinic acid ligands, were obtained by the reaction of styrene–divinylbenzene copolymer (2 wt.% of crosslinker, expanded gel structure) bearing phenylphosphinic acid groups with trimethylchlorosilane and then with an appropriate electrophile. Reactions were carried out with ethyl oxalylchloride, ethyl bromopyruvate and ethyl-4-chloroacetoacetate and resulted in resins with multidentate ligands, having acid capacities of 3.57, 3.86 and 3.33 mmol/g, respectively. These resins, obtained in 66–93% yield, were used in the removal of Cu(II), Cd(II), Ni(II), Zn(II), Mg(II) and Ca(II) from nitric acid solutions and their performance compared to the performance of the parent, phenylphosphinic acid resin. It was found that resin 1, obtained in the reaction of phenylphosphinic resin with ethyl oxalylchloride, has the highest affinity towards all of the above cations, whereas the remaining two resins performed similarly to the phenylphosphinic acid resin. New, functionalized resins were also used in an ester form for the removal of Au(III), Cu(II), Fe(III) and Ag(I) chlorocomplexes from hydrochloric acid solutions of various concentrations. It was found that resins in an ester form are able to selectively complex tetrachloroaurate from 0.5 to 6.0 M HCl. For example, ester form of resin 3 ( P=1.78, OH=0.64, %=70.30), removes the above mentioned chlorocomplexes from 1 M HCl solution. Log K d values are 4.08, 0.95, 0.97 and 1.46 for Au(III), Cu(II), Fe(III) and Ag(I), respectively.

Thermodynamic and kinetic study of copper(II) complexes with N-methylene(phenylphosphinic acid) derivatives of cyclen and cyclam

Equilibria in the Cu 2+–H 4L 1 and Cu 2+–H 4L 2 systems, where H 4L 1 is 1,4,7,10-tetraaza-cyclododecane-1,4,7,10-tetrayl-tetramethylene-tetrakis(phenylphosphinic acid) and H 4L 2 is 1,4,8,11-tetraaza-cyclotetradecane-1,4,8,11-tetrayl-tetramethylene-tetrakis(phenylphosphinic acid), were investigated by glass electrode potentiometry at 25°C ( I=0.1 mol dm −3 KNO 3). A simple chemical model with the metal:ligand molar ratio 1:1 was found in the systems. The presence of main species, [CuL 1] 2− (log β=20.37(4)) and [CuL 2] 2− (log β=17.19(2)), was also confirmed by MALDI-TOF/MS. The dissociation kinetics of the complexes was followed by spectrophotometry and a mechanism of the dissociation was proposed. Activation parameters (activation enthalpy and entropy) of the dissociation were estimated. For the Cu 2+–H 4L 1 system, the complex dissociation starts after protonation of the phosphinic pendant arms and its mechanism is similar to the decomplexation of [Cu(cyclen)] 2+. The Cu 2+ complex with H 4L 2 is kinetically much less stable. The proton transfer from the phosphinic pendant arm to the azacycle plays a significant role in the reaction mechanism of both the complexes.

New Macrocyclic Ligands. XII. Phosphonic and Phosphinic Acid Pendant Arm Derivatives of Mixed Donor Macrocycles: Towards New Selective Reagents for Lead(II)

The synthesis of new bis-phosphonic, -phosphinic and -phenylphosphinic acid pendant-arm derivatives of a 15-membered, N 2 O 2 -donor macrocyclic ring is described. Thermodynamic stabilities of the 1:1 (metal:ligand) complexes of cobalt(II), nickel(II), zinc(II), silver(I), cadmium(II) and lead(II) with the bisphenylphosphinic acid derivative have been determined in 95% methanol (I = 0.1, NEt4ClO 4; 25°C). Along the above metal-ion series, this ligand forms its most stable complex with lead(II).