In situ backscattered electron imaging study of the effect of annealing on the deformation behaviors of Ni electroformed from additive-free and saccharin-containing sulfamate solutions

The Ni samples were electroformed from additive-free(AF) and saccharin-containing(SC) sulfamate solutions, respectively. In situ backscattered electron(BSE) imaging, electron backscatter diffraction(EBSD), and electron-probe microanalysis(EPMA) were used to investigate the effect of annealing on the deformation behaviors of the AF and SC samples. The results indicate that columnar grains of the as-deposited AF sample had an approximated average width of 3 μm and an approximated aspect ratio of 8. The average width of columnar grains of the as-deposited SC sample was reduced to approximately 400 nm by the addition of saccharin to the electrolyte. A few very-large grains distributed in the matrix of the SC sample after annealing. No direct evidence indicated that S segregated at the grain boundaries before or after annealing. The average value of the total elongations of the SC samples decreased from 16% to 6% after annealing, whereas that of the AF samples increased from 18% to 50%. The dislocation recovery in grain-boundary areas of the annealed AF sample was reduced, which contributed to the appearance of microvoids at the triple junctions. The incompatibility deformation between very-large grains and fine grains contributed to the brittle fracture behavior of the annealed SC Ni.

An Electrochemical Cinnamyl C—H Amination Reaction Using Carbonyl Sulfamate

An electrochemical cinnamyl C—H amination reaction in the absence of transition metal catalyst and oxidant was reported. The choice of carbonyl sulfamate as nitrogen source is the key to achieve desired chemoselectivity. A series of terminal amine derivatives are prepared using this protocol and the sulfonyl group can be removed with basic hydrolysis. The reaction is suggested to proceed via a continuous anodic oxidation, deprotonation, anodic oxidation, and intermolecular nucleophilic addition pathway, demonstrating the first example of electrochemical cinnamyl C—H amination.

AMMONIUM SULFAMATE FLAME RETARDED POLYAMIDE 6:MORPHOLOGY AND THERMAL DEGRADATION

The effect of ammonium sulfamate （AS） content on the flame retardancy of polyamide 6 （PA6） was studied. It is found that the limiting oxygen index （LOI） of PA6 increases with the increase of AS content and the flame retardancy of PA6 is significantly improved. The morphology of the residues after combustion was examined by means of scanning electron microscopy （SEM）. SEM results show that AS facilitates the formation of the intumescent char layer with honeycomb-like structure, which inhibits the transfer of heat and mass, and thus improves the flame retardancy of PA6. The thermal degradation of AS flame retarded PA6 was studied by thermogravimetric analysis （TGA）. The Kissinger method was applied to estimate the activation energy （Ea） of the degradation. The activation energy of the thermal degradation of PA6 decreases by adding AS, indicating that AS can promote the degradation of PA6.

Extracting copper from copper oxide ore by a zwitterionic reagent and dissolution kinetics

Sulfamic acid （SA）, which possesses a zwitterionic structure, was applied as a leaching reagent for the first time for extracting copper from copper oxide ore. The effects of reaction time, temperature, particle size, reagent concentration, and stirring speed on this leach- ing were studied. The dissolution kinetics of malachite was illustrated with a three-dimensional diffusion model. A novel leaching effect of SA on malachite was eventually demonstrated. The leaching rate increased with decreasing particle size and increasing concentration, reac- tion temperature and stirring speed. The activation energy for SA leaching malachite was 33.23 kJ/mol. Furthermore, the effectiveness of SA as a new reagent for extracting copper from copper oxide ore was confirmed by experiment. This approach may provide a solution suitable for subsequent electrowinning. In addition, results reported herein may provide basic data that enable the leaching of other carbonate miner- als of copper, zinc, cobalt and so on in an SA system.

硅胶键合N-丙基二乙烯氨基磺酸作为可回收固体酸催化剂催化合成α-氨基腈(英文)

Silica-bonded N-propyl diethylenetriamine sulfamic acid (SBPDSA) is employed as a recyclable catalyst to synthesize α-aminonitriles. These syntheses involved one-pot condensation of an aldehyde, an amine, and trimethylsilyl cyanide under mild reaction conditions at room temperature. SBPDSA was recycled seven times in the condensation of benzaldehyde, aniline, and trimethylsilyl cyanide without reduction of its catalytic activity.

((3-(3-硅胶丙基)硫基)丙基)硫酸酯作为可回收催化剂用于合成4,4'-芳亚甲基-双(1H-吡唑-5-醇)(英文)

Sulfuric acid ([3-(3-silicapropyl)sulfanyl]propyl)ester is employed as a recyclable catalyst for the condensation reaction between aromatic aldehydes and 3-methyl-l-phenyl-5-pyrazolone. This condensation reaction was performed in ethanol under refluxing conditions giving 4,4'-alkylmethylene-bis(3-methyl-5-pyrazolones) in 74-90% yields. The heterogeneous catalyst was recycled and used in eleven runs for the reaction between benzaldehyde and 3-methyl-l-phenyl-5-pyrazolone without losing catalytic activity.

Sulfamic acid as a reusable and green catalyst for efficient and simple synthesis of 2-substituted-2,3-dihydroquinazolin-4(1H)-ones in water or methanol

A series of 2,3-dihydroquinazolin-4（1H）-ones have been synthesized in good to excellent yields through direct cyclocondensation of anthranilamide and aryl aldehydes or ketones in water or methanol under mild conditions.The reaction was efficiently promoted by 10 mol%sulfamic acid（SA,H_2NSO_3H） and the catalyst could be recovered easily after the reactions and reused without evident loss of reactivity.

Sulfamic acid:An efficient,cost-effective and green catalyst for crossed-aldol condensation of ketones with aromatic aldehydes under solvent-free

Aromatic aldehydes undergo crossed-aldol condensation with ketones in the presence of catalytic amount of sulfamic acid （SA） to afford the corresponding α,β-unsaturated aldol products under solvent-free conditions in good to high yields at 45-80 ℃.

An Efficient and Solvent-Free Reaction for Synthesis of Bis（indol-3-yl）methanes Catalyzed by Sulfamic Acid

SA （sulfamic acid） catalyzes the reaction of indole with aldehyde and ketone to afford bis（indol-3-yl）methanes in good to excellent yields under solvent-free condition at ambient temperature.

An Efficient, Three-component One-pot Preparation of 1,4-Dihydropyridines Containing Novel Substituted Pyrazole under Sulfamic Acid Catalysis

An efficient approach to 1,4-dihydropyridines containing novel substituted pyrazole is achieved via threecomponent reaction of pyrazolyl aldehyde, β-ketoester, and ammonium acetate in one-pot under sulfamic acid catalysis.

Silica-bonded N-propyl sulfamic acid as an efficient recyclable catalyst for the synthesis of 3,4-dihydropyrimidin-2-(1H)-ones/thiones under heterogeneous conditions

Silica-bonded N-propyl sulfamic acid （SBNPSA） catalyzed one-pot three component Biginelli condensation of different substituted aromatic aldehydes with ethyl acetoacetate and urea/thoiurea to the respective 3,4-dihydropyrimidin-2-（lH）-ones and thiones in environment friendly procedure is described. The facile reaction conditions, simple isolation and purification procedures of this method make it a good option for the svnthesis of dihydropyrimidinones.

The Three-component One-pot Synthesis of 4,6-Diarylpyrimidin-2(1h)-ones and 9-Phenyl-8-oxa-10,12-diaza-tricyclo[7.3.1.0^(2,7)]trideca-2(7),3,5-trien-11-one

1 Results Pyrimidinones (PMs) are a class of important heterocycles which have been well documented throughout the literature due to their biological importance. They exhibit a wide range of pharmaceutical and therapeutic properties[1].A rapid and efficient one-pot method for the synthesis of 4,6-diarylpyrimidin-2(1H)- ones and related heterocycles is described.The condensation of acetophenone derivatives,aldehydes and urea in the presence of sulfamic acid was employed to synthesize a variety of pyrimid...

An Efficient and Green One-pot Synthesis of 12-Aryl-8,9,10,12-tetra hyd robenzo[a]xanthen-11 -one Deriva- tives Promoted by Sulfamic Acid in [BMIM]BF4 Ionic Liquid

An efficient and green procedure for the synthesis of novel 12-aryl-8,9,10,12-tetrahydrobenzo[a]xanthen- 11- one derivatives has been described through one-pot condensation of 2-naphthol, arylaldehyde and 5,5-dimethyl- cyclohexane-l,3-dione in the presence of sulfamic acid （NH2SO3H） in ionic liquid 1-n-butyl-3-methylimidazolium tetrafluoroborate （[BMIM]BF4）. These reactions proceed with good yields under short reaction time. Furthermore, the green catalytic system can be recycled specific times with no decreases in yields and reaction rates.

Sulfamic acid as a green,reusable catalyst for stepwise,tandem&one-pot solvent-free synthesis of pyrazole derivatives

Sulfamic acid（SA） is a bi-functional, cost-effective and reusable green catalyst for the synthesis of 4-（pyrazol-4-yl）methylenepyrazol-5（4H）-one derivatives by one-pot, three-component condensation of pyrazol-4-carbaxaldehydes, b-ketoesters and phenyl hydrazine（Route-I）. In addition to this method,another simple condensation of pyrazol-4-carbaxaldehydes with pyrazolone in the presence of SA under the solvent-free condition in good yield is reported. The merits of these protocols are mild conditions,non-aqueous workup, high yields, easy availability of the catalyst, no chromatographic separation and inexpensive solid acid catalyst. Furthermore, SA could be recycled and reused for five times without losing its catalytic activity.