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Co(III) catalysed asymmetric ring-opening of epichlorohydrin by salicylaldehyde derivatives: reversal of enantioselectivity and rate acceleration on addition of AlCl3
Asymmetric catalysis salicylaldehyde Co(III) salen aryloxy alcohols epoxide ring-opening
2010/12/3
Using asymmetric Cobalt(III) salen catalysts, the ring-opening of epichlorohydrin by 2,3-dihydroxybenzal- dehyde and 2,4- dihydroxybenzaldehyde was found to occur at the phenolic groups most distant f...
'Solid phase extraction of Copper, Nickel and Cobalt in water samples after extraction using surfactant Coated alumina modified with Indane-1,2,3-trione 1,2-dioxime and determination by flame atomic absorption
Solid phase extraction surfactant coated alumina atomic absorption spectrometry
2010/10/19
A simple method for simultaneous pre-concentration of Cu, Ni, and Co metal ions prior to their determination by flame atomic absorption spectrometry is reported. The method is based on the extraction ...
Effect of Various Substituents on Intramolecular 1,1-Vinylboration, Synthesis of 1-Silacyclobutene Derivatives.
Alkynylsilanes triorganoboranes hydroboration organoboration
2010/10/19
The reaction of 1-boryl-1-alkenyl chlorosilane derivatives with alkynyllithium reagents [Li-C≡C-R3 (R3 = Ph, SiMe3) ] at low temperature (–78 ◦C) affords alkenyl(alkyn-1-yl)silanes. These compou...
Synthesis and crystal structure of a novel multimodal ligand, 6,6'-bis(2-(di(pyridin-2-yl)methylene)-1-methylhydrazinyl)-2,2'-bipyridine and its copper(I) complex, {[Cu3L2](PF6)3?3H2O} (1)
Bipyridine derivatives hydrazone dipyridyl ketone metal complexes
2010/10/19
The single crystal X-ray structure of the novel multimodal ligand 6,6’-bis(2-(di(pyridin-2-yl)methylene)-1-methylhydrazinyl)-2,2’-bipyridine, C34H28N10 (L), was determined at 120 (2) K. The ligand pos...
Synthesis and Characterizations of Some New 2,4-Dihydro-[1,2,4]-triazol-3-one Derivatives and X-Ray Crystal Structures of 4-(3-Phenyl allidene amino)-5-thiophen-2-yl-methyl-2,4-dihydro-[1,2,4]triazol-3-one
1,2,4-Triazole aldehydes ethyl bromoacetate bromo acetophenone
2010/10/19
Compounds 2 were synthesised via the reaction of 4-amino-5-thiophen-2-yl-methyl-2,4-dihydro-[1,2,4]-triazol-3-one (1) with aldehydes. Compounds 3 and 4 were obtained from compounds 2 with bromo acetop...
Synthesis, Spectroscopic Characterization, Mass Spectrometry and Crystal Structure of N-{[(4-bromophenyl) amino]carbonothioyl}benzamide
Thiourea derivative X-ray structure determination mass fragmentation
2010/10/19
N-{[(4-bromophenyl)amino]carbonothioyl}benzamide was synthesized and characterized by IR, 1 H- and 13C-NMR, mass spectrometry, and elemental analysis. The crystal structure was determined from single ...
Bromodimethylsulfonium Bromide/ Tetrabutylammonium Nitrite: An Efficient Catalyst Mixture for the Nitration of Phenols
Bromodimethylsulfonium bromide nitration, nitrophenol tetrabutylammonium nitrite
2010/10/19
Nitrophenols were obtained via direct nitration of phenols with tetrabutylammonium nitrite in the presence of bromodimethylsulfonium bromide at room temperature in high yields under aprotic conditions...
Synthesis and super-swelling behavior of a novel low salt-sensitive protein-based superabsorbent hydrogel: collagen-g-poly(AMPS)
Collagen hydrogel swelling 2-acrylamido-2-methylpropanesulfonic acid
2010/10/19
Superabsorbent polymers are obtained by the graft copolymerization of 2-acrylamido-2-methylpropanesulfonic acid (AMPS) monomer onto collagen, using ammonium persulfate as a free radical initiator in t...
Co(III) Catalysed Asymmetric Ring-Opening of Epichlorohydrin by Salicylaldehyde Derivatives: Reversal of Enantioselectivity and Rate Acceleration on Addition of AlCl3
Asymmetric catalysis salicylaldehyde Co(III) salen
2010/10/19
Using asymmetric Cobalt(III) salen catalysts, the ring-opening of epichlorohydrin by 2,3-dihydroxybenzaldehyde and 2,4- dihydroxybenzaldehyde was found to occur at the phenolic groups most distant fro...
以端羟基聚乙二醇(PEG)为反应底物，甲苯为溶剂，在80℃下用二氯亚砜对端羟基氯代；再在N,N-二甲基甲酰胺中，与叠氮化钠进行叠氮化反应得到端叠氮基聚乙二醇（N3PEG）。用FT-IR、13CNMR、DSC等对产物进行了表征。结果表明，聚乙二醇端羟基峰消失，同时出现明显的叠氮基特征峰；聚乙二醇端羟基活泼氢的吸收峰消失，说明聚乙二醇端羟基叠氮化反应完全，转化率高；端叠氮基聚乙二醇的熔点有所下降，有利...
以咪唑为原料，用硝硫混酸硝化制备4,5-二硝基咪唑，再将4,5-二硝基咪唑与氨气反应生成其铵盐水合物。用红外光谱、核磁共振光谱、元素分析等对其结构进行了表征，讨论了反应温度、反应时间、混酸摩尔比等因素对目标产物得率的影响。结果表明，通过优化工艺，产物的总得率达到71.6%以上。硝硫混酸的摩尔比对产品的得率影响最大，温度的影响次之，反应时间影响最小。最佳工艺条件为：反应温度为110~115℃；反应时...
选用HNO3/CH2Cl2有机硝化体系研究羟烷基纤维素的酯化过程。用XRD技术和jade5.0分析软件测试分析羟乙基纤维素（HEC）和二羟丙基纤维素（DHPC）的结晶情况，用显微镜观察酯化中形成凝胶的颗粒状态。研究表明，HEC和DHPC的酯化分为两个阶段，在达到凝胶临界点之前的酯化与纤维素类似，在达到凝胶临界点时，含氮量最高，形成凝胶之后，含氮量迅速降低。摩尔取代度（MS）越大，含氮量越低，并且M...
N2O5硝解三丙酰基三氮杂环己烷制备RDX
有机化学 N2O5 三丙酰基三氮杂环己烷 RDX 硝解 炸药
2014/3/4
以三丙酰基三氮杂环己烷为原料，N2O5/HNO3为硝解剂制备了RDX。分别考察了硝解剂浓度、反应物配比、反应温度和反应时间对RDX产率的影响。结果表明，当N2O5与HNO3的摩尔比为1∶10，N2O5与三丙酰基三氮杂环己烷的摩尔比为6∶1，反应温度为45℃，反应1h，RDX的最高产率可达92.7%，纯度为98.5%。
SUSTAINING A CONTROVERSY: THE NON-CLASSICAL ION DEBATE
organic chemistry explanation Non-classical Ions controversy
2011/9/7
This paper examines a scientific controversy that raged for twenty years in physical organic chemistry during the second half of the twentieth century. After explaining what was at stake in the Non-Cl...
Synthesis and characterization of novel triazol compounds containing a thiophen ring as potential antifungal agents and the structure of 2-(2-hydroxy-2-p-tolyethyl)-5-(thiophen-2-ylmethyl)- 4-(4H-1,2,4-triazol-4-yl)-2H-1,2,4-triazol-3(4H)-one
Synthesis 1,2,4-triazole-3-one NaBH4 LiAlH4 antimicrobial activity
2010/10/18
A series of new 4-(3,5-disubstitue-4H-1,2,4-triazol-4-yl)- 5-(thiophen-2-yl-methyl)-2H-1,2,4-triazol-3(4H)-ones (3a-c) were obtained by reaction N'-1-ethoxy-2-thiophen-2-yl-ethylydene hydrazino carbox...