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991.
Jin-Ming Yang Shun-Jun Ji Da-Gong Gu Shun-Yi Wang 《Journal of organometallic chemistry》2005,690(12):2989-2995
A facile Michael addition of ferrocenylenones with aliphatic amines under ultrasound irradiation in the absence of solvent and catalyst at room temperature can afford 1-ferrocenyl-3-amino carbonyl compounds rapidly in high yields, which is also efficient in the aza-Michael reaction of other α,β-unsaturated carbonyl compounds such as chalcone, carboxylic ester, etc. However, aromatic amines do not undergo the conjugate addition at all, and the reactions under existing methods do not proceed or take place in low yield after a long reaction time. Apart from experimental simplicity, generality and selectivity, the advantages of this methodology are the rapid, environmentally benign and less expensive processes, which will contribute to the progress of green chemistry. 相似文献
992.
Alkylation of 2-mercaptopyridine with 1,2-dibromoethane affords a cyclic dihydrothiazolopyridinium salt that can serve as a precursor of 2-aminopyridines. Its reaction with primary or secondary amines, either neat or in DMSO, under mild conditions gives the title compounds. 相似文献
993.
Robert Kaplánek Tomáš B?íza Martin Havlík Vladimír Král 《Journal of fluorine chemistry》2007,128(3):179-183
Three-fold polyfluoroalkylated amines were prepared from tris(hydroxymethyl)aminomethane (TRIS) in five steps including perfluoroalkyl iodide addition to the corresponding allyl derivative, reduction of C-I bond and deprotection of the amino group. They can be easily converted to the corresponding isocyanates. 相似文献
994.
染色皮革,纺织品上禁用偶氮染料的高效液相色谱测定方法 总被引:5,自引:1,他引:4
德国联邦消费者保护和兽医研究所规定不得使用能还原出20种芳香胺的偶氮染料,针对这一规定研究了同时测定20种芳香胺的高效液相色谱方法,进行了样品预处理和色谱条件优化的探讨。方法检出限小于30×10-6,满足进出口商品检验的需要。方法回收率一般为70%~100%,相对标准偏差为95%~210%。 相似文献
995.
本文以反应性氯甲基化纤维为基体,合成丁氮含量分别为4.06、4.92mmol/g的含胺基(-NH2)及乙二胺基(-NHC2H4NH2)功能纤维.静态吸附实验结果表明:在pH2.0乙二胺基纤维对Au3+的吸附量达最大(620mg/g),含胺基纤维的吸附量为248mg/g;WAXD证实它们对Au3+都有还原作用;含乙二胺基纤维对吸附态Au3+的还原百分率最大值为91%(pH4.0),而含胺基纤维在pH2.0的还原百分率为100%,但pH<0.6后,含乙二胺基纤维对Au3+无还原作用;含乙二胺基纤维对Au3+的吸附量随溶液温度升高而增大;在乙醇、1、4-氧六环、乙酸乙酯中含乙二胺基纤维对Au3+的吸附量分别为42、143、0mg/g,且在乙醇中它对Au3+有还原作用.吸附动力学实验结果表明:吸附初期为快速离子交换过程,中期为螯合吸附占主导地位,后期则是氧化还原吸附占优势.在扫描电子显微镜可观察到部分吸附在含乙二胺基纤维上的金聚集成粒状. 相似文献
996.
In mononuclear [Zn(C10H9N3)2(N3)2]·H2O, the zinc atom has an approximate octahedral geometry, coordinated with four pyridyl nitrogen atoms derived from two bis(2‐pyridyl)amine molecules and two terminal nitrogen donors of the azide anions. Hydrogen‐bonding interactions extend this structure to form a double‐layer architecture. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
997.
James D. R. Talbot 《Journal of polymer science. Part A, Polymer chemistry》2004,42(14):3579-3586
This article investigates the role of solvation effects in the autocatalysis reaction of the epoxy–amine cure reaction. A single‐phase three component model was developed encompassing a two‐component reaction mix and a single polymeric product. The reaction was modelled as an SN2 reaction. Association of the nucleophile with each component in the reaction was defined via a binding constant. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 3579–3586, 2004 相似文献
998.
Synthetic utility of the Fischer-type carbene complexes of chromium for the preparation of nitrogen-containing compounds is demonstrated. Alkoxy carbene complexes reacted with imines to give (optically active) 3-pyrrolines and beta-methoxy allylic amine derivatives in good yields. The amino carbene complexes reacted with alpha,beta-unsaturated aldehydes to give substituted pyrroles in good yields. 相似文献
999.
The synthesis of C6F13CH2C(CFCFCF3)N-C2H4-C6H5 (11) from the addition of H2N-C2H4-C6H5 onto C6F13CH2CF2CF2CFHCF3 (3) is presented. C6F13CH2CF2CF2CFHCF3 (3) and C6F13CH2CF2CF(CF3)CF2H (3′) isomers were obtained from the thermal stepwise cotelomerization of vinylidene fluoride and hexafluoropropene with C6F13I, followed by the selective reduction of the iodine end atom. At 200 °C, the 3/3′ molar ratio reached 9.0. In contrast to selective reduction, dehydrofluorination led to various derivatives, which were characterized by 1H NMR and 19F NMR spectroscopy, and hence a reaction pathway could be suggested. The grafting of an amine containing an aromatic ring onto the cotelomers based on VDF and HFP occurred selectively on VDF/HFP diad and, in some instances a further step involving the formation of an imine was observed. The addition of 2-phenylethylamine onto the dehydrofluorinated intermediates was found to be quantitative. 相似文献
1000.
Chemical synthesis of glycoproteins from readily available materials is a powerful method for obtaining a pure product with full control of its atomic structure. Sugar-assisted ligation (SAL) is an emerging approach that allows the synthesis of a large glycopeptide from two unprotected fragments. Contrary to other ligation methods that are limited to the use of a cysteine residue or depend on external auxiliary, SAL takes advantage of the existing sugars in glycopeptides to promote proximity between the two peptides to facilitate an amide bond formation. 相似文献