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81.
N- aryl substituted benzenesulfamides are often used as heating-sensitive recording material1, thermal printing material2, sensitizer3 and developer4. Moreover, some of the benzenesulfamides have antifungal activities5. Many methods have been described for preparation of sulfamides. They are used to carry out in solvent8 or in solid phase condition9. These methods required solvent or solid support and even required heating or cooling. At the same time, the process of these methods is complex. Now we have developed a new method to prepare N-aryl substituted toluenesulfamides under solvent-free conditions.In recent years, solvent-free technology has gained popularity in organic synthesis. For instance,solidstate reaction and microwave reaction have received considerable attention. Solvent-free synthesis of amides has been reported10-11. This technology has many advantages such as high efficiency and selectivity, easy separation and environmental acceptability. All these merits are in accord with green chemistry's requirements of energy-saving, high efficiency and environmental benefits.In our paper, we used a simple and efficient method for preparing N-aryl substituted toluenesulfamides under solvent-free conditions, as a replacement for classic solvent, which gives many environmental benefits.All reactions were completed at room temperature by co-grinding in an agate mortar for 3-20min and the results are shown in Table 1.In conclusion, we have developed an efficient and convenient method of preparation N-aryl substituted toluenesulfamides in high yields. It symbols an improvement for synthesis of benzenesulfamides. 相似文献
82.
YAN Xiaomin ZHAO Lin SHAO Jianhui TAN Xin SONG Zhengxiao School of Chemical Engineering Technology Tianjin University Tianjin China Slichem Liquid Material Co. Ltd. Shijiazhuang China 《Chinese Journal of Reactive Polymers》2004,(Z1)
1. INTRODUCTION Methionine, namely 2-amido-4-thiomethyl butyric acid with a structure of CH3SCH2CH2CHCOOH, is one of the essential amino acids and has two natural enantionmers, D and L-methionine. The mixture of L- and D-isomers can be used as analeptics or nutritive additives to maintain the equilibrium of amino acids of feed [1,2]. L-methionine can release active methyl and accelerate the synthesis of choline, which further speeds up the conversion of the lipid accumulated in liv… 相似文献
83.
NianYuanTAN XiaoMingXIAO ZeLinLI TakekoMATSUMURA-INOUE 《中国化学快报》2004,15(6):687-690
A new cobalt(Ⅱ) complex with tridentate ligand 2, 6-bis (benzimidazol-2-yl)pyridine has been synthesized by microwave irradiation method and characterized by elemental analysis,electrochemical and spectral methods. The binding of the complex with calf thymus DNA has also been investigated by absorption and fluorescence spectra. 相似文献
84.
Baker‘s yeast mediated reduction of optically active diketone is described. The two keto groups are efficiently differentiated and the ee value of the recovered material is considerably raised. It affords highly optically active key intermediates efficiently for the synthesis of natural polyhydroxylated agarofuran products. 相似文献
85.
86.
Thermal oxidation of polyethylene filled with dispersed copper and containing an amine antioxidant was studied. The concentration ranges in which the catalytic effect of the metal on the polymer oxidation or the stabilizing effect of the antioxidant prevails were determined. Under certain conditions, dispersed copper enhances the stabilizing effect of the antioxidant. 相似文献
87.
Lin Huaxin 《数学年刊B辑(英文版)》1993,14(3):387-396
The author studies the problem whether a multiplier of a hereditary C^*-subalgebra B of a C^*-algebra A can be extended to a multiplier of A. One related problem is the Hahn-Banach extension theorem for Hilbert modules over C^*-algebras. It is shown that every self-dual Hilbert module over W^*-algebra or an injective C^*-algebra is injective. 相似文献
88.
89.
90.
V.I. Fernández A. Iucci C.M. Naón 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,30(1):53-56
We present an extension of the Tomonaga-Luttinger model in which left and right-moving particles have different Fermi velocities.
We derive expressions for one-particle Green's functions, momentum-distributions, density of states, charge compressibility
and conductivity as functions of both the velocity difference ε and the strength of the interaction β. This allows us to identify
a novel restricted region in the parameter space in which the system keeps the main features of a Luttinger liquid but with
an unusual behavior of the density of states and the static charge compressibility κ. In particular κ diverges on the boundary
of the restricted region, indicating the occurrence of a phase transition.
Received 20 May 2002 / Received in final form 23 August 2002 Published online 19 November 2002 相似文献