Complete Assignment of the 1H and 13C NMR Spectra of Carthamin Potassium Salt Isolated from Carthamus tinctorius L.

Carthamin potassium salt isolated from Carthamus tinctorius L. was purified by an improved traditional Japanese method, without using column chromatography. The ¹H and ¹³C nuclear magnetic resonance (NMR) signals of the pure product were fully assigned using one- and two-dimensional NMR spectroscopy, while the high purity of the potassium salt and deprotonation at the 3′ position of carthamin were confirmed by atomic adsorption spectroscopy and nano-electrospray ionization mass spectrometry.     

Analysis of organic salts by laser ionization

Alkali salts of 1-hexyl sulfonate were ionized by laser irradiation and the positive ions were analyzed by time-of-flight mass spectrometry. The sodium, potassium, rubidium and cesium salts produce relatively simple spectra. The major organic ions observed are due to the salt plus a cation or the dimer plus a cation. No molecular or fragment ions were detected. The instrumentation and the method of interpreting these data are described.     

Study on flame-retardant mechanism of polycarbonate containing sulfonate-silsesquioxane-fluoro retardants by TGA and FTIR

The flame retardancy of bisphenol A polycarbonate (PC) containing potassium diphenylsulfone sulfonate (KSS), poly(aminopropyl/phenylsilsesquioxane) (PAPSQ) and poly(vinylidenefluoride) (PVDF) was measured by limited oxygen index (LOI) and examined according to UL94. A high LOI and UL94 V-0 rating for 1.6 mm thickness samples were obtained by a combined use of equivalent KSS, PAPSQ and PVDF at 0.1-0.3 wt% loading, respectively. The improvement in flame retardancy of PC compositions arose from the synergistic interaction of three additives. Thermogravimetric analysis (TGA) indicated that the combination decreased the activation energy (E) of PC degradation and elevated the thermal degradation rate of PC to ensure the formation of an insulating carbon layer. FTIR analysis showed that the LOI char of PC containing the three additives took on a highly cross-linking aromatic ester and ether structure.     

Conversion of Magnus salt into diamminedichloroplatinum(II) isomers in aqueous solution

The conditions inducing conversion of Magnus salt into diamminedichloroplatinum(II) isomers were studied. Syntheses of cis-diamminedichloroplatinum(II) and trans-diamminedichloroplatinum(II), which are used to prepare potassium or ammonium amminetrichloroplatinate(II), are described. The identity and structure of diamminedichloroplatinum(II) isomers were verified by elemental analysis, X-ray powder diffraction, and IR and UV spectroscopy. A workflow for preparing potassium or ammonium amminetrichloroplatinate(II) from diamminedichloroplatinum(II) isomers was developed. This workflow appreciably increases the product yield due to the return of unused Magnus salt to the main synthesis flow.     

Synthesis and characterisation of water soluble ferrocenes: Molecular tuning of redox potentials

A range of novel water-soluble alkylated ferrocene sulfonate compounds are reported. Mono- and di-sulfonation on a series of alkyl ferrocenes produced 1,1′-dimethyl ferrocene sulfonate, 1,1′-dimethyl ferrocene disulfonate, 1,1′-diethyl ferrocene sulfonate, 1,1′-diethyl ferrocene disulfonate, t-butyl ferrocene sulfonate, t-butyl ferrocene disulfonate, ethyl ferrocene sulfonate, ethyl ferrocene disulfonate, n-butyl ferrocene sulfonate and n-butyl ferrocene disulfonate. All compounds were characterized by NMR spectroscopy, UV/Vis spectroscopy and electrochemical analysis. ¹H and ¹³C NMR studies have revealed the formation of several isomers with sulfonation occurring on positions α and β to the alkyl substituent or on the unsubstituted cyclopentadienyl ring. Variation of the alkyl group allowed the isomeric pattern to be tuned such that the final products followed either electronic or steric control. Cyclic voltammetry of the resulting products showed that the redox potential of the iron centre can be easily manipulated by changing the substituents on the cyclopentadienyl rings. This result has significant implications in the future development of homogenous redox mediators for sensing applications.     

Effect of a novel flame retardant containing silicon and nitrogen on the thermal stability and flame retardancy of polycarbonate

A novel flame retardant (PSiN), containing silicon and nitrogen, was synthesized using N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane and diphenylsilanediol through solution polycondensation and it was added to polycarbonate (PC). The structure and thermal properties of PSiN were characterized by fourier transform infrared spectroscopy and thermogravimetric analysis (TG) tests. The effect of PSiN on the flame retardancy and thermal behaviors of PC was investigated by limited oxygen index (LOI), vertical burning test (UL-94), and TG tests. The results showed that the flame retardancy and the thermal stability of PC are improved with the addition of PSiN. When 1 mass% PSiN and 0.5 mass% diphenylsulfone sulfonate (KSS) are incorporated, the LOI value of PC is found to be 46, and class V-0 of UL-94 test is passed. The char structure observed by scanning electron microscopy indicated that the surface of the char for PC/KSS/PSiN system holds a firmer and denser char structure when compared with neat PC and PC/KSS system.     

Sodium paeoniflorin sulfonate, a process derived artefact from paeoniflorin

Sodium paeoniflorin sulfonate 2 was isolated from processed, but not unprocessed, Paeonia lactiflora roots and characterized by mass spectrometry and NMR spectroscopy. A notable and characteristic downfield shift in the ¹H NMR was observed for the hydrogens β to the alkoxysulfonate moiety in 2 and in other model compounds.     

磺化聚苯乙烯和聚碳酸酯共混物相容性的红外光谱研究

磺化聚苯乙烯和聚碳酸酯共混物相容性的红外光谱研究刘杰何嘉松（中国科学院化学研究所工程塑料国家重点实验室北京１０００８０）关键词付立叶变换红外光谱，相容性，高分子共混物，离子 偶极相互作用由于热力学原因，高分子对往往是不相容的．高分子共混物若要溶...     

Isothermal mass crystallization of ammonium and potassium nitrates from Tergitol NP-4-based water-in-oil microemulsions

A procedure is elaborated for preparing powders of ammonium and potassium nitrates with microsized particles and stable sols with particle sizes of 7–16 nm based on isothermal mass crystallization from Tergitol NP-4-stabilized water-in-oil microemulsions in decane. The crystallization process is studied by turbidimetry and photon-correlation spectroscopy. The isolated powders are characterized by scanning electron microscopy, while sols and microemulsions are studied by photon-correlation spectroscopy. Evaporation of water from microemulsion droplets upon stirring water-in-oil micellar solutions at 25–45°C is shown to be the reason for the salt crystallization. It is ascertained that the time of the onset of crystallization and the morphology of resulting particles depend on temperature, content of an aqueous pseudophase, and the nature of a salt. A desolubilization-emulsion hypothesis is proposed for explaining the formation of nanoparticle powders and organosols.     

Synthesis and characterization of polycarbonates derived from N,N′-m-phenylenebis(3-hydroxybenzamide) and 4,4-bis(4-hydroxyphenyl)pentanoic acid anilide

The polycarbonates of N,N′-m-phenylenebis(3-hydroxybenzamide) (PBHB) and 4,4-bis(4-hydroxyphenyl)pentanoic acid anilide (BHPAA) were prepared by interfacial polymerization. They were characterized by inherent viscosity measurements, infra-red spectroscopy, differential scanning calorimetry and thermogravimetric analysis. The PBHB polycarbonate was significantly more stable thermally than the BHPAA polycarbonate.     

Correlated substituent rotation in the 1,2-benzenedisulfonate anion: the structure of the hydrated potassium salt

Structure determinations have previously been recorded on the dipotassium and potassium tetramethylammonium salts of 1,2-benzenedisulfonic acid (methanol solvate and hydrate, respectively), as a platform for examining the gear-like interactions of adjacent sulfonate substituents on the aromatic ring. The present report records a single crystal X-ray study of the hydrated potassium salt, showing it to be 8K₂[(O₃S)₂C₆H₄] · 11H₂O, with eight independent anions in the asymmetric unit, enabling a more broadly-based consideration of substituent dispositions.     

Electrochemical characterisation of novel water-soluble ruthenocene complexes: An anion-dependent response

The synthesis and voltammetric exploration of water-soluble ruthenocene sulfonate is reported. ¹H and ¹³C NMR, mass spectroscopy and elemental analysis data are given to confirm the successful synthesis of this novel compound. Furthermore, it is found that the cyclic voltammetric response is strongly dependent on the size of anion in solution. Sodium toluene sulfonate is found to be capable of forming a charge-transfer complex with the oxidized ruthenocenium ion. In the presence of all other anions, follow-on reactions are observed.     

Crystal Structures of the Potassium and Silver Salts of Nitroform

The solid state structures of three nitroformate (NF) salts were determined using single crystal X‐ray crystallography. The NF anion was found to be a non‐planar moiety which adopts either the commonly observed C_2v conformation or distorted propeller conformation (D₃) in the case of the silver salts, or, a C₂ conformation in the case of the potassium salt. This latter C₂ conformation has been uniquely observed for potassium nitroformate. All structures exhibit cation‐anion interactions that influence the structure of the anion. The ¹³C and ¹⁴N NMR spectra of the NF anion show broad singlets, which indicates the equivalence of the nitro groups in solution within the NMR time‐scale. In addition, the vibrational and mass spectra of potassium nitroformate and silver nitroformate monohydrate were recorded. Furthermore, the gaseous decomposition products of potassium nitroformate at 25 °C were detected using IR spectroscopy and mass spectrometry.     

Enhanced copper surface protection in aqueous solutions containing short-chain alkanoic acid potassium salts

The ability of dissolved potassium monocarboxylate salts to produce surface passivation and to inhibit aqueous corrosion of copper was studied. The electrochemical measurements indicate that the inhibiting efficiency of these compounds, with a general formula Cn-1H2n-1COOK or CnK (n=3...12), is dependent on the hydrocarbon chain length. The inhibiting efficiency was higher for a longer hydrocarbon chain of n-alkanoic acid. The degree of copper protection was found to increase with an increase in n-alkanoic acid potassium salt concentration; the optimum concentration of potassium dodecanoate (C12K) in sulfate solutions was found to be 0.07 M. The protective layers formed at the copper surface subsequent to exposure in various n-alkanoic acid potassium salt solutions were characterized by contact angle measurements, electrochemical impedance spectroscopy, X-ray photoelectron spectroscopy, and Fourier transform infrared reflection spectroscopy. Pronounced copper protection was attributed to the growth of a protective film on the copper surface, containing both copper oxides and copper carboxylate compounds. It is suggested that the organic molecules enhance copper protection by covering copper oxides with a thin and dense organic layer, which prevents water molecules or aggressive anions from interacting with the copper surface.     

Spectres de vibration et liaison hydrogène du cyclobutane 1-1 dicarboxylate acide de potassium

The crystal structure of potassium hydrogen cyclobutane 1-1 dicarboxylate has been determined by X-ray analysis. This acid salt has a short unsymmetrical intermolecular hydrogen bond with O … O = 2,53 Å, but the carboxylic residues show only small differences in dimensions. Polycrystalline samples of CB(COO)₂HK-1,1 and its O-deuterated analog have been studied by i.r. and Raman spectroscopy. An assignment of the bands is given, the details of the hydrogen bond bands are discussed; in particular the isotopic ettect (νOH/ νOD ∼ 1), the combination bands in the region 1900–2500 cm⁻¹ and the carbonyl region. It suggested that the acid salt belongs to Speakman's pseudo A type.     

Sulfonated RAFT Copolymers as Heparin Mimetics: Synthesis,Reactivity Ratios,and Anticoagulant Activity

The glycosaminoglycan heparin is a clinically important anticoagulant drug, primarily used to reduce the risk of blood clots (thrombosis) during surgery. Despite its importance in medicine and its continuous use over many decades, heparin suffers from several limitations associated with its heterogeneity and its extraction from animal tissues. In order to address these limitations, reversible addition‐fragmentation chain transfer polymerization is utilized to prepare a library of heparin mimetic copolymers from the sulfonated monomers sodium 4‐styrene sulfonate, potassium‐3‐sulfopropyl acrylate, potassium‐3‐sulfopropyl methacrylate, and sodium‐2‐acrylamido‐2‐methyl‐1‐propane sulfonate. Copolymers are prepared using combinations of two different monomers in various ratios. Monomer reactivity ratios are also determined for some representative monomer combinations, and all polymers are characterized by ¹H NMR spectroscopy and gel permeation chromatography. The anticoagulant activities of the copolymers are determined by activated partial thromboplastin time and thrombin clotting time assays and structure–activity relationships are explored.     

Synthesis of linear polyformal and copoly(carbonate formal) from polycarbonate

A linear, high molecular weight polyformal is readily synthesized by direct transformation of commercially available polycarbonate. The reaction is best carried out in dibromomethane with 8.0 equiv. of potassium hydroxide pellets in the presence of a phase-transfer catalyst at 90–95°C. A random copoly(carbonate formal) can also be obtained simply by reducing the amount of potassium hydroxide used in the reaction. The molecular weight of the resulting polymer is governed by the starting polycarbonate.     

Chemical transformations of N-morpholinylacetic acid hydrazide and steric structure of its derivatives

The reaction of N-morpholinylacetic acid hydrazide with various isothiocyanates and potassium thiocyanate resulted in the corresponding potentially biologically active thiosemicarbazide derivatives. Potassium N′-(2-morpholin-4-ylacetyl)hydrazinocarbothioate was synthesized and involved into heterocyclization in acidic environment to yield cyclic 5-(morpholinomethyl)-1,3,4-thiadiazole-2-thione. The structure of the synthesized compounds was established by IR, ¹H NMR spectroscopy, mass spectrometry, and XRD analysis.     

Synthesis of poly(styrene sulfonate) brushes.

Dense poly(styrene sulfonate sodium salt) brushes were prepared on silicone wafers using a two-step procedure: polystyrene (PS) chains, terminated by a reactive trichlorosilane group, were first covalently grafted, and then the PS brush was converted to a poly(styrene sulfonate) brush by a soft sulfonation reaction. Ellipsometry and infrared spectroscopy in ATR were used to characterize the samples and to optimize the procedure: in particular, the sulfonation was shown to be homogeneous along the chain backbone and the neutralization complete. In some cases, the polymer layer revealed to be quite fragile: the chains were pulled out of the brush. A consolidation treatment which consisted in grafting oligomers inbetween the long PS chains significantly increased the robustness of the layer. This might be relevant for industrial applications.     

Synthesis of 3,7-disubstituted hexahydro- and tetrahydro-2<Emphasis Type="Italic">H</Emphasis>-indazoles from cross-conjugated dienones

The oxidation of 3,7-disubstituted hexahydroindazoles with potassium hexacyanoferrate(III) afforded previously unknown tetrahydro-2H-indazole derivatives. A novel ring contraction reaction leading to 2,3-diazaspiro[4.4]non-3-en-1-one derivatives was discovered. The product structure was proved by NMR spectroscopy, mass spectrometry, and X-ray analysis.