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1.
Synthesis, Structure, and some Reactions of N-(N′,N′,N″,N″-tetramethyl)guanidinyl-substituted Phosphoryl Compounds The tetramethylguanidinyl-substituted phosphoryl compounds 1 – 10 were prepared in the reaction of the appropriate chlorophosphoryl compounds with either N′,N′,N″,N″-tetramethylguanidine (HTMG) or N-trimethylsilyl-(N′,N′,N″,N″-tetramethyl)guanidine (TMSTMG). With methyl iodide 1 reacted with N-alkylation to give the ammonium salt 11. 1 reacted with BF3 · Et2O at both imino nitrogen atoms with formation of the bis-BF3-adduct 12 . The X-ray structure determination of phenylphosphonic acid-bis(N′,N′,N″,N″-tetramethylguanidinide) 3 shows shortened PN-bonds and widened PNC-angles, consistent with the partial double bond character of the PN-bond.  相似文献   

2.
By reaction of N-(N′,N′,N″,N″-tetramethyl)guanidinyl-substituted phosphines with diorganochlorophosphines, organodichlorophosphines, p-tolylsulfenylchloride and phenylselenylchloride a variety of stable phosphonium chlorides with a P–E (E = P, S, Se) bond were obtained. In one case, performing this reaction in the presence of sodium tetraphenylborate led to the corresponding phosphonium tetraphenylborate. All compounds were characterised by multinuclear NMR and elemental analysis. The selenophosphonium chloride 4 a of the trihydrate was further characterised by a single crystal X-ray analysis. The P–Se bond is very long [193.0(3), 193.3(3) pm in two independent fomula units]. The water molecules and the chloride anions form hydrogen bonded layers.  相似文献   

3.
A novel ligand, N,N,N′,N′,N″‐penta (methyl acrylate) diethylenetriamine (MA5‐DETA), was synthesized by the reaction of diethylenetriamine with methyl acrylate in almost quantitive yield. The polymerizations of methyl methacrylate with MA5‐DETA as the ligand and α,α‐dichlorotoluene (DCT) and ethyl 2‐bromoisobutyrate (2‐EBiB) as the initiators, respectively, under different conditions were examined. The polymerization with CuCl/MA5‐DETA/DCT was closely controlled in bulk and gave polymers with quite narrow molecular weight distributions (Mw/Mn's) of 1.16–1.29. The polymerization with the system CuBr/MA5‐DETA/EBiB in bulk gave high activity. However, the system was not well controlled and gave the polymers with Mw/Mn = 1.35–1.53. The solution polymerization in anisole with CuBr/MA5‐DETA/EBiB showed a better‐controlled nature. Moreover, the addition of CuBr2 into the aforementioned system can further improve its controllability. The Mw/Mn's of the resulting polymers ranged from 1.11 to 1.21. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 1963–1969, 2004  相似文献   

4.
N,N,N′,N′‐tetraalkyaminoazoxybenzene derivatives were conveniently prepared by the coupling of N,N‐dialkylnitrosoaniline in the presence of acetone and KOH. The reaction mechanism was proposed and investigated, and the structure of compound 3b was also confirmed by single crystal X‐ray diffractometry.  相似文献   

5.
A new triphenylamine‐containing aromatic diamine monomer, N,N‐bis(4‐aminophenyl)‐N,N′‐bis(4‐tert‐butylphenyl)‐1,4‐phenylenediamine, was synthesized by an established synthetic procedure from readily available reagents. A novel family of electroactive polyamides with di‐tert‐butyl‐substituted N,N,N,N′‐tetraphenyl‐1,4‐phenylenediamine units were prepared via the phosphorylation polyamidation reactions of the newly synthesized diamine monomer with various aromatic or aliphatic dicarboxylic acids. All the polymers were amorphous with good solubility in many organic solvents, such as N‐methyl‐2‐pyrrolidinone (NMP) and N,N‐dimethylacetamide, and could be solution‐cast into tough and flexible polymer films. The polyamides derived from aromatic dicarboxylic acids had useful levels of thermal stability, with glass‐transition temperatures of 269–296 °C, 10% weight‐loss temperatures in excess of 544 °C, and char yields at 800 °C in nitrogen higher than 62%. The dilute solutions of these polyamides in NMP exhibited strong absorption bands centered at 316–342 nm and photoluminescence maxima around 362–465 nm in the violet‐blue region. The polyamides derived from aliphatic dicarboxylic acids were optically transparent in the visible region and fluoresced with a higher quantum yield compared with those derived from aromatic dicarboxylic acids. The hole‐transporting and electrochromic properties were examined by electrochemical and spectro‐electrochemical methods. Cyclic voltammograms of the polyamide films cast onto an indium‐tin oxide‐coated glass substrate exhibited two reversible oxidation redox couples at 0.57–0.60 V and 0.95–0.98 V versus Ag/AgCl in acetonitrile solution. The polyamide films revealed excellent elcterochemical and electrochromic stability, with a color change from a colorless or pale yellowish neutral form to green and blue oxidized forms at applied potentials ranging from 0.0 to 1.2 V. These anodically coloring polymeric materials showed interesting electrochromic properties, such as high coloration efficiency (CE = 216 cm2/C for the green coloring) and high contrast ratio of optical transmittance change (ΔT%) up to 64% at 424 nm and 59% at 983 nm for the green coloration, and 90% at 778 nm for the blue coloration. The electroactivity of the polymer remains intact even after cycling 500 times between its neutral and fully oxidized states. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2330–2343, 2009  相似文献   

6.
The reaction of [Pd(CH3CN)2Cl2] with N ‐functional group‐substituted 2‐iminomethylpyrrole‐based ligands, namely N 1‐((1H‐pyrrol‐2‐yl)methylene)‐N 3,N 3‐dimethylpropane‐1,3‐diamine (LA), N 1‐((1H‐pyrrol‐2‐yl)methylene)‐N 3‐methyl‐N 3‐phenylpropane‐1,3‐diamine (LB), N ‐((1H‐pyrrol‐2‐yl)methylene)‐3‐(methylthio)propan‐1‐amine (LC) and N ‐((1H‐pyrrol‐2‐yl)methylene)‐3‐methoxypropan‐1‐amine (LD), resulted in [Ln PdCl] (Ln  = LA–LD) complexes in high yield via N─H bond activation of pyrrole moiety without use of base. [Ln PdCl] existed as monomeric four‐coordinated complexes with slightly distorted square planar geometries around the palladium metal center. The ligands show N ,N ′,X ‐tridentate binding mode to the palladium metal center to give two fused ring metallacycles. [LBPdCl] gave the highest activity (3.29 × 105 g PMMA (mol Pd)−1 h−1) for a methyl methacrylate (MMA) polymerization in the presence of modified methylaluminoxane at 60 °C compared to the other Pd(II) analogues, and resulted in PMMA with higher molecular weight (M w = 7.16 × 105 g mol−1) and narrower polydispersity index. Syndiotactic‐enriched PMMA resulted in all cases.  相似文献   

7.
《Electroanalysis》2006,18(16):1620-1626
A polyvinylchloride membrane sensor based on N,N′‐bis(salecylidene)‐1,2‐phenylenediamine (salophen) as membrane carrier was prepared and investigated as a Al3+‐selective electrode. The sensor exhibits a Nernstian response toward Al(III) over a wide concentration range (8.0×10?7–3.0×10?2 M), with a detection limit of 6.0×10?7 M. The potentiometric response of the sensor is independent of the pH of the test solution in the pH range 3.2–4.5. The electrode possesses advantages of very fast response and high selectivity for Al3+ in comparison with alkali, alkaline earth and some heavy metal ions. The sensor was used as an indicator electrode, in the potentiometric titration of aluminum ion and in determination of Al3+ contents in drug, water and waste water samples.  相似文献   

8.
The solvatochromic compound [Cu(tfmh)Me4en]ClO4 (tfmh? denotes the anion of 1,1,1-trifluoro-6-methyl-2,4-heptanedione) was prepared and its structure has been determined from three-dimensional X-ray diffraction data. The structure consists of discrete [Cu(tfmh)Me4en]+ monomeric units and perchlorate ions. The copper(II) ion is surrounded by the two nitrogen atoms of the diamine molecule and the two oxygen atoms of the β-dionato anion. The N,N,N′,N′-tetramethyl-1,2-diaminoethane, Me4en, coordinates as bidentate ligand through the nitrogen atoms and adopts the gauche conformation and λ configuration. The CuN2O2 chromophore is virtually planar. The compound crystallizes in the monoclinic system (space group P21/c) with a = 11.9520(2), b = 14.6600(2), c = 17.2240(4) Å, β = 135.72(2)°, Z = 4 and V = 2107.01(7) Å3.  相似文献   

9.
The molecular structures of trichlorido(2,2′:6′,2′′‐terpyridine‐κ3N,N′,N′′)gallium(III), [GaCl3(C15H11N3)], and tribromido(2,2′:6′,2′′‐terpyridine‐κ3N,N′,N′′)gallium(III), [GaBr3(C15H11N3)], are isostructural, with the GaIII atom displaying an octahedral geometry. It is shown that the Ga—N distances in the two complexes are the same within experimental error, in contrast to expected bond lengthening in the bromide complex due to the lower Lewis acidity of GaBr3. Thus, masking of the Lewis acidity trends in the solid state is observed not only for complexes of group 13 metal halides with monodentate ligands but for complexes with the polydentate 2,2′:6′,2′′‐terpyridine donor as well.  相似文献   

10.
N,N′‐Bis(difuroxano[3,4‐b:3′,4′‐d]phenyl)oxalic amide was synthesized via acylation, nitration, azidation, and pyrolysis‐denitrogenation from the starting materials of oxalyl chloride and 3,5‐dichloroaniline, under mild reaction conditions, with the yields of 81.0%, 82.0%, 86.0% and 81.7% respectively. The title compound and its precursors were characterized by 1H NMR, IR, MS, and elemental analysis. The title compound has a density of 1.92 g·cm?3 by a suspension method, a standard formation enthalpy of 979 kJ·mol?1 calculated by Gaussian programs, a detonation velocity of 8.17 km·s?1, and a detonation pressure of 31 GPa obtained by Kamlet Equation. The thermal decomposition reactions of the title compound at different heating rates were tested by differential scanning calorimetry (DSC). The kinetics parameters of the pyrolysis of the compound were calculated by Kissinger's method. The values of apparent activation energy (Ea) and pre‐exponential constant (A) were 226.7 kJ·mol?1 and 1023.17 s?1 respectively. It was presupposed that N,N′‐bis(difuroxano[3,4‐b:3′,4′‐d]phenyl)oxalic amide would be a promising high energetic explosive with low sensitivity.  相似文献   

11.
Starting with 3,3′,4,4′‐biphenyltetracarboxylic dianhydride and methyl aminobenzoate, we synthesized a novel rodlike imide‐containing monomer, N,N′‐bis[p‐(methoxy carbonyl) phenyl]‐biphenyl‐3,3′,4,4′‐tetracarboxydiimide (BMBI). The polycondensation of BMBI with dimethyl terephthalate and ethylene glycol yielded a series of copoly(ester imide)s based on the BMBI‐modified poly(ethylene terephthalate) (PET) backbone. Compared with PET, these BMBI‐modified polyesters had higher glass‐transition temperatures and higher stiffness and strength. In particular, the poly(ethylene terephthalate imide) PETI‐5, which contained 5 mol % of the imide moieties, had a glass‐transition temperature of 89.9 °C (11 °C higher than the glass‐transition temperature of PET), a tensile modulus of 869.4 MPa (20.2 % higher than that of PET), and a tensile strength of 80.8 MPa (38.8 % higher than that of PET). Therefore, a significant reinforcing effect was observed in these imide‐modified polyesters, and a new approach to higher property polyesters was suggested. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 852–863, 2002; DOI 10.1002/pola.10169  相似文献   

12.
An all solid‐state Ag(I) ion‐selective electrode has been prepared by simply immersing a glassy carbon rod coated with PVCAc, which contained plasticizer and additive but no ionophore, into the AgNO3 solution. The response of the electrode was linear with a Nernstian slope of 60.25 mV/decade within the concentration range from 1×10?1 to 1×10?5 M and with a detection limit of 4.25×10?6 M. The stability as an effect of various cations was defined. The electrode is suitable for use in high acidic solutions (pH<1 to 7) and has successfully been applied for the determination of silver(I) concentrations in different samples.  相似文献   

13.
Three copper(II) complexes, [Cu2(OAc)4L2] · 2CH3OH ( 1 ), [CuBr2L′2(CH3OH)] · CH3OH ( 2a ), and [CuBr2L′2(DMSO)] · 0.5CH3OH ( 2b ) {L = N‐(9‐anthracenyl)‐N′‐(3‐pyridyl)urea and L′ = N‐[10‐(10‐methoxy‐anthronyl)]‐N′‐(3‐pyridyl)urea} have been synthesized by the reaction of L with the corresponding copper(II) salts. Complex 1 shows a dinuclear structure with a conventional “paddlewheel” motif, in which four acetate units bridge the two CuII ions. In complexes 2a and 2b , the anthracenyl ligand L has been converted to an anthronyl derivative L′, and the central metal ion exhibits a distorted square pyramidal arrangement, with two pyridyl nitrogen atoms and two bromide ions defining the basal plane and the apical position is occupied by a solvent molecule (CH3OH in 2a and DMSO in 2b ).  相似文献   

14.
Novel electrochemical sensors based on carbon paste impregnated with metallopthalocyanine (MPc, M=Co, Fe) complexes, have been constructed for the assay of anti‐HIV drug 2′,3′‐dideoxyinosine (didanosine, DDI). Both modified electrodes showed electrocatalytic activity towards the oxidation of dideoxyinosine in phosphate buffer pH 7.4 with a working concentration range of 10?6–10?4 mol/L and a detection limit of 10?7 mol/L magnitude order. The sensor proved to be highly reliable for the assay of the purity of DDI ‐ raw material as well as for the uniformity content test of Videx tablets.  相似文献   

15.
Two approaches to the formation of ruthenium(II) complexes containing ligands with conjugated 2,2′:6′,2″-terpyridine (tpy), alkynyl and bithienyl units have been investigated. Bromination of 4′-(2,2′-bithien-5′-yl)-2,2′:6′,2″-terpyridine leads to 4′-(5-bromo-2,2’-bithien-5′-yl)-2,2′:6′,2″-terpyridine (1), the single crystal structure of which has been determined. The complexes [Ru(1)2][PF6]2 and [Ru(tpy)(1)][PF6]2 have been prepared and characterized. Sonogashira coupling of the bromo-substituent with (TIPS)CCH did not prove to be an efficient method of preparing the corresponding complexes with pendant alkynyl units. The reaction of 4′-ethynyl-2,2′:6’,2″-terpyridine with 5-bromo-2,2′-bithiophene under Sonogashira conditions yielded ligand 2, and the heteroleptic ruthenium(II) complex [Ru(2)(tpy)][PF6]2 has been prepared and characterized.  相似文献   

16.
A new ion selective electrode for salicylate based on N,N'-(aminoethyl)ethylenediamide bis(2-salicylideneimine) binuclear copper(Ⅱ) complex [Cu(Ⅱ)2-AEBS] as an ionophore was developed. The electrode has a linear range from 1.0 × 10^-1 to 5.0 ×10^-7 mol·L^- 1 with a near-Nemstian slope of ( - 55 ±1 ) mV/decade and a detection limit of 2.0 × 10-7 mol·L^-1 in phosphorate buffer solution of pH 5.0 at 25 ℃. It shows good selectivity for Sal^- and displays anti-Hofmeister selectivity sequence: Sal^-〉SCN^-〉 ClO4^- 〉I^-〉 NO2^- 〉Br^-〉 NO3^- 〉Cl^-〉 SO3^2- 〉 SO4^2- The proposed sensor based on binuclear copper(Ⅱ)complex has a fast response time of 5-10 s and can be used for at least 2 months without any major deviation. The response mechanism is discussed in view of the alternating current (AC) impedance technique and the UV-vis spectroscopy technique. The effect of the electrode membrane compositions and the experimental conditions were studied. The electrode has been successfully used for the determination of salicylate ion in drug pharmaceutical preparations.  相似文献   

17.
Adducts of N, N′ -dimethyl-2, 2′-bisimidazole (DMBIm) with diethyl- and dibutyl-tin(IV) dihalides (Cl, Br) have been isolated and characterized. IR data for [SnR2X2(DMBIm)] compounds are in keeping with a six-coordinate tin atom with DMBIm acting as a bidentate ligand, whereas in [(SnR2X2)2(DMBIm)] the tin is five-coordinate and DMBIm acts as a bridging ligand. Measurements of conductivity in acetonitrile show the adducts to behave as non-ionogens in this solvent. NMR data show them to undergo dissociation in CDCl3.  相似文献   

18.
A new N‐phenylated amide (N‐phenylamide) unit containing aromatic diamine, N,N′‐bis(3‐aminobenzoyl)‐N,N′‐diphenyl‐1,4‐phenylenediamine, was prepared by the condensation of N,N′‐diphenyl‐1,4‐phenylenediamine with 3‐nitrobenzoyl chloride, followed by catalytic reduction. Two series of organosoluble aromatic poly(N‐phenylamide‐imide)s and poly(N‐phenylamide‐amide)s with inherent viscosities of 0.58–0.82 and 0.56–1.21 dL/g were prepared by a conventional two‐stage method and the direct phosphorylation polycondensation, respectively, from the diamine with various aromatic dianhydrides and aromatic dicarboxylic acids. All polyimides and polyamides are amorphous and readily soluble in many organic solvents such as N,N‐dimethylacetamide and N‐methyl‐2‐pyrrolidone. These polymers could be solution cast into transparent, tough, and flexible films with high tensile strengths. These polyimides and polyamides had glass‐transition temperatures in the ranges of 230–258 and 196–229 °C, respectively. Decomposition temperatures of the polyimides for 10% weight loss all occurred above 500 °C in both nitrogen and air atmospheres. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2564–2574, 2002  相似文献   

19.
《Electroanalysis》2005,17(17):1534-1539
The construction, performance, and applications of a novel ytterbium(III) sensor based on N‐(2‐pyridyl)‐N′‐(2‐methoxyphenyl)‐thiourea (PMT), as an excellent carrier, in plasticized poly(vinyl chloride) PVC matrix, is described. The influences of membrane composition and pH on the potentiometric response of the sensor were investigated. The sensor exhibits a nice Nernstian response for Yb(III) ion over a wide concentration range of 4 decades of concentration (1.0×10?6–1.0×10?2 M), and a detection limit of 5.0×10?7 M. The response time of the electrodes is between 8 and 10 s, depending on the concentration of ytterbium(III) ions. The proposed sensor can be used for about 8 weeks without any considerable divergence in potential. The sensor revealed very good selectivity for Yb(III) in the presence of several metal ions. The best performance was observed for the membrane containing; 30% PVC, 59% o‐nitrophenyloctyl ether (NPOE) as solvent mediator, 7% PMT, and 4% sodium tetraphenyl borate (NaTPB). It was successfully applied as indicator electrodes in the potentiometric titration of Yb(III) with EDTA and for the determination of fluoride ion in two mouth wash formulations. The proposed La(III) sensor was found to work well under laboratory conditions. It was also used as an indicator electrode in titration of a 1.0×10?4 M of Yb(III) with a standard EDTA solution (1.0×10?2 M). It was also used for determination of Yb(III) ion in Xenotime .  相似文献   

20.
《Electroanalysis》2006,18(11):1091-1096
N‐(2‐Pyridyl)‐N′‐(4‐methoxyphenyl)‐thiourea (PMPT) was found to be a suitable neutral ion carrier for the construction of a highly selective and sensitive La(III) membrane sensor. Poly(vinyl chloride) (PVC) based membranes of PMPT with potassium tetrakis (p‐chlorophenyl) borate (KTpClPB) as an anionic excluder and oleic acid (OA), dibutyl phthalate (DBP), benzyl acetate (BA) and o‐nitrophenyloctyl ether (NPOE) as plasticizing solvent mediators were constructed and investigated as La(III) membrane sensors. A membrane composed of PMPT‐PVC‐KTpClPB‐BA with the ratio 8.0 : 35.0 : 3.0 : 54.0 works well over a very wide concentration range (4.0×10?8 to 1.0×10?1 M) with a Nernstian slope of 19.6±0.2 mV per decade of activity between pH values of 4.0 and 9.0. The detection limit of the sensor was calculated to be 2.0×10?8 M (ca. 3.0 ppb). The sensor displays very good discrimination toward La(III) ions with regard to most common metal ions and lanthanide ions. The proposed sensor shows a short response time for whole concentration range (ca. 12 s). For evaluation of the analytical applicability of the La(III) sensor, it was successfully used as an indicator electrode for the titration of La(III) ions with EDTA. It was also applied to the determination of fluoride content of two mouth wash preparation samples and monitoring of La(III) ions in some binary and ternary mixtures.  相似文献   

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