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1.
Thermal decomposition of transition metal malonates, MCH2C2O4?xH2O and transition metal succinates, M(CH2)2C2O4?xH2O (M=Mn, Fe, Co, Ni, Cu, Zn) has been studied employing TG, DTG, DTA, XRD, SEM, IR and Mössbauer spectroscopic techniques. After dehydration, the anhydrous metal malonates and succinates decompose directly to their respective metal oxides in the temperature ranges 310–400 and 400–525°C, respectively. The oxides obtained have been found to be nanosized. The thermal stability of succinates have been found to be higher than that of the respective malonates. 相似文献
2.
Yanling Liu 《Tetrahedron》2010,66(7):1447-9608
A highly efficient enantioselective Friedel-Crafts alkylation of indoles with alkylidene malonates has been developed using chiral N,N′-dioxide L4-scandium(III) complex as the catalyst, giving the corresponding products in high yields with excellent enantioselectivities (up to 99% yield and 95% ee). The product 3a was facilely converted into several interesting compounds, such as tryptamines, indolepropionic acids and β-carbolines. It is noteworthy that the seven-membered β-carboline-like compound has been synthesized for the first time. Based on the crystal structure of the chiral N,N′-dioxide L10-scandium(III) complex, the proposed transition state and possible catalytic cycle were presented to elucidate the reaction mechanism. 相似文献
3.
Stereochemical control of the addition of silyl- and stannyl metals to chiral γ-alkoxy-alkylidene malonates proved to be dependant on the nature of the counter ion and of the solvent but in an unpredictable way. 相似文献
4.
A new approach to the construction of polycyclic skeletons of fused azines with nitrogen at the bridgehead based on a novel
reaction of cyclic Schiff's bases (1-alkyl-substituted 3,4-dihydroisoquinolines) with α-aminomethylenecarbonyl compounds (2-aminomethylene-cyclohexane-1,3-diones
or aminomethylenemalonic ester) was developed.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1358–1360, July, 1997. 相似文献
5.
Fused 2-pyrones4, obtained by the thermal condensation of ketones1 with reactive malonates2, rearrange above 200°C to yield condensed dihydroxynaphthalines5. The latter compounds can be oxidized to give 3-hydroxy-1,4-naphthoquinone-5-alkanoic acids. The reaction of ketone8 with magic malonates2 or chlorocarbonyl ketene9 affords the pyrones11 in low yields. The 2-pyrones11 could not be rearranged to13; a possible explanation for this behaviour is presented.
Herrn Prof. emer. Dr.E. Ziegler, der vor 30 Jahren erstmals die ketenoide Reaktionsweise von Malonsäurederivaten beschrieb [16], in Dankbarkeit und Freundschaft gewidmet. 相似文献
6.
The effect of silicon on C–C bond formation between carbonyl compounds and allyltrimethylsilane was investigated. Treatment of 1,3-diketones, β-ketoesters or malonates with allyltrimethylsilane in the presence of ceric ammonium nitrate (CAN) in methanol produced the corresponding allylated products. Furthermore, introduction of Mn(OAc)3 · 2H2O into those reactions for replacement or assistance of CAN afforded silicon-containing cyclopentanes in 51–75% yields. A sequential process involving allylation, free-radical cyclization and elimination was also developed by use of CAN/Mn (OAc)3 · 2H2O/Cu(OAc)2 · H2O. Accordingly, β-ketoesters or malonates were allowed to react with allylsilanes in acetic acid to give silicon-containing cyclopentanes with an exo methylene unit in 52–71% yields. These reactions involved carbocationic and carboradical intermediates, of which formation and chemical activities were controlled by a β-silyl group. © 1997 by John Wiley & Sons, Ltd. 相似文献
7.
Randhawa B. S. Kaur Sandeep Bassi P. S. 《Journal of Thermal Analysis and Calorimetry》1999,55(3):789-796
The thermal decomposition of strontium and barium malonates has been studied isothermally and non-isothermally employing simultaneous
TG-DTG-DTA, DSC, XRD and IR spectroscopic techniques. DSC of these malonates has been recorded both in oxygen and nitrogen
atmospheres. The decomposition is a single step process and the end product formed is carbonate. The energy of activation
and frequency factor values for the decomposition of strontium malonate are 547 kJ mol−1 and 1041 s−1 respectively. The activation energy and frequency factor values for isothermal dehydration of barium malonate sester-hydrate
are 57–111 kJ mol−1 and 107–1012 s−1 respectively and the corresponding values for decomposition from DSC are 499.5 kJ mol−1 and 1044 s−1 respectively. The higher thermal stability of strontium malonate as compared to that of barium salt is ascribed to its being
anhydrous so that decomposition proceeds without restructuring. Their thermal stabilities have also been compared with that
of respective oxalate salts.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
8.
M. N. Elinson S. K. Feducovich T. A. Zaimovskaya A. N. Vereshchagin S. V. Gorbunov G. I. Nikishin 《Russian Chemical Bulletin》2005,54(7):1593-1598
Electrolysis of alcoholic solutions of dialkyl malonates and arylidene- or alkylidenemalononitriles in the presence of NaBr
in an undivided cell gave dialkyl esters of 3-substituted 2,2-dicyanocyclopropane-1,1-dicarboxylic acids in 60–90% yields.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1547–1552, July, 2005. 相似文献
9.
微波作用下亚烃基丙二酸亚异丙酯的合成 总被引:2,自引:0,他引:2
报导了微波辐射下丙二酸亚异丙酯与羧基化合物进行了Knoevenagel缩合反应,高产率地合成了亚烃基丙二酸亚异丙酯。 相似文献
10.
以I2为催化剂,原甲酸三乙酯、芳(杂环)胺和亚磷酸二乙酯为原料,室温无溶剂条件下,一锅合成了系列芳(杂环)胺亚甲基双膦酸四乙酯,收率96%~99%。 当I2物质的量分数为5%时,产物收率最高。 本方法底物适用范围广,操作简单。 I2作为催化剂,安全高效。 相似文献