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991.
Jung-Hoon Oh Mun-Chual Rho Hyeong Kyu Lee Jae Nyoung Kim Sang-Hun Jung 《Tetrahedron letters》2004,45(38):7077-7079
Asymmetric synthesis of four possible stereoisomers of (9,10)-epoxyheptadecan-4,6-diyn-3-one was accomplished, and the absolute configuration of the naturally occurring (9R,10S)-epoxyheptadecan-4,6-diyn-3-one (1) was elucidated. 相似文献
992.
A new effective method is provided for the synthesis of macrocyclic aliphatic disulfide oligomers by catalytic oxidation of aliphatic dithiols with oxygen in the presence of a copper‐amine catalyst. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
993.
A novel compound Ni(phen)(H2O)(V2O6) has been hydrothermally synthesized and structurally determined to be a two-dimensional compound, which contains {V2O6}n2n- chains interconnected by nickel(Ⅱ) complexes via oxygen atoms. The crystallographic data measured by single-crystal X-ray diffraction analysis are as follows: C12H10N2NiO7V2, Mr=454.81, monoclinic, space group P21/c, a=0.784 6(3), b=2.103 6(8), c=0.942 3(4) nm, β=112.872(5)°, V=1.433 0(10) nm3, Z=4, Dc=2.104 Mg·m-3, μ(Mo Kα)=2.615 mm-1, F(000)=904, T=298(2) K, 4 480 reflections collected, 2 470 independent (Rint=0.032 2), the final R=0.058 4 and wR2=0.145 7 for 2 303 observed reflections with I>2σ(I). CCDC: 192520. 相似文献
994.
995.
The review surveys methods for the synthesis, as well as structures and properties of sulfur-containing iron nitrosyl complexes serving as models of active sites of [Fe—S] nitrosyl proteins, which are potential donors of nitrogen monoxide.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2326–2345, November, 2004. 相似文献
996.
A New Technique of Synthesizing 10—Hydroxy—5—methyl—5,10—dihydrophenophosphazine 10—Oxide 总被引:1,自引:0,他引:1
ZhiGangYIN DeFengZHAO 《中国化学快报》2003,14(4):347-350
10-Hydroxy-5-methyl-5,10-dihydrophenophosphazine 10-oxide(1)was prepared by a new technique of treating 10-methoxy-5,10-dihydrophenophosphazine 10-oxide(2)with an equivalent of NaH in anhydrous DMF,and then at 120℃ for 3-4h,which not only avoided poisonous and expensive methyl iodide used in literature,but made the consumption of NaH greatly decrease as well.The possible reaction mechanism was also described.The chemical structure of 1 was confiremed by IR,NMR,and mass spectroscopy. 相似文献
997.
O. V. Gusev L. N. Morozova T. A. Peganova P. V. Petrovskii N. A. Ustynyuk 《Russian Chemical Bulletin》1994,43(3):474-477
A mixture ofendo-H andexo-H isomers (1a and1b) of the (4-C5Me5H)PtCl2 complex was prepared by the reaction of K2PtCl4 with C5Me5H in MeOH. The mixture of isomers reacts with CpTl in the presence of TiBF4 to give a novel complex, [(4-C5Me5H)Pt(5-C5H5)]+BF4
–, as a mixture ofendo-H- andexo-H-isomers (2a and2b). The data of1H and13C NMR spectroscopy of the resulting complexes are discussed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 514–517, March, 1994. 相似文献
998.
John M. Adams Keith Martin Richard W. McCabe 《Journal of inclusion phenomena and macrocyclic chemistry》1987,5(6):663-674
Suitably modified smectite clays can be very selective catalysts for a wide range of organic reactions. While it has long been known that such materials can act as Bronsted and Lewis acids, it has been shown recently that they are also effective Diels-Alder catalysts. A selection of illustrative reactions is given which emphasises their wide range of use, their selectivity, and the ease of work-up after reaction. In each case, mechanistic information is presented, e.g., on the site of reaction (whether interlayer or surface), rate determining steps, etc. The regiochemical consequences of the restricted reaction space are stressed.Based on material presented at the Fourth International Symposium on Inclusion Phenomena and the Third International Symposium on Cyclodextrins, Lancaster, U.K., 20–25 July 1986. 相似文献
999.
在异维生素C钠(D-VcNa)的合成过程中,以SO42-/S iO2-TiO2复合固体超强酸作为酯化反应催化剂,2-酮基-D-葡萄糖酸(2-KGA)和甲醇为原料,采用精馏脱水酯化工艺,不断除去酯化过程中产生的水。催化剂的最佳焙烧温度为550℃,催化剂用量为2.5%;反应时间3~4 h,产品收率为88.6%,催化剂的重复使用性较好,催化体系优于硫酸法。 相似文献
1000.
Synthesis and Characterization of Dual Acidic Ionic Liquids 总被引:1,自引:0,他引:1
Xiao Hua WANG Guo Hong TAO Zi Yan ZHANG Yuan KOU 《中国化学快报》2005,16(12):1563-1565
Novel ionic liquids with dual acidity, of which the cation contains Brφnsted acidity and anions contain Lewis acidity were synthesized. These ionic liquids obtained were identified by NMR, FF-IR, SDT and FAB-MS. Their acidities were determined by pyridine probe on IR spectrography. 相似文献