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991.
S. Yu. Ryabova E. Yu. Khmel’nitskaya N. A. Rastorgueva N. B. Grigor’ev V. G. Granik 《Russian Chemical Bulletin》2004,53(12):2830-2833
Electrochemical reduction of 1-aryl-2-oxo-1,2,3,6-tetrahydro[1,4]diazepino[6,5-b]indole 4-oxides, 2-oxo-1-phenyl-1,2,3,6-tetrahydro[1,4]diazepino[6,5-b]indole, and 2-oxo-1-phenyl-1,2,3,4,5,6-hexahydro[1,4]diazepino[6,5-b]indole was studied. The results obtained were compared with previous data for the reduction of 4-oxides with formamidinesulfinic acid.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2715–2718, December, 2004. 相似文献
992.
T. V. Mitkina D. Yu. Naumov O. A. Gerasko F. M. Dolgushin C. Vicent R Llusar M. N. Sokolov V. P. Fedin 《Russian Chemical Bulletin》2004,53(11):2519-2524
The inclusion compound of macrocyclic cavitand cucurbit[8]uril (CB[8]) with the nickel(II) complex containing the tetraazamacrocyclic ligand cyclam, {[Ni(cyclam)]@CB[8]}Cl2··16H2O (1), and the inclusion compounds of CB[8] with the copper(II) bis-ethylene-diamine complex, {trans-[Cu(en)2(H2O)2]@CB[8]}Cl2·{CB[8]}·42H2O (2a) and {trans-[Cu(en)2(H2O)2]@CB[8]}Cl2·17H2O (2b), were synthesized and characterized by X-ray diffraction analysis, IR and ESR spectroscopy, and electrospray mass spectrometry. Guest—host inclusion compounds can be directly synthesized starting from a metal complex and cucurbit[8]uril, as was exemplified by the preparation of compounds 2a and 2b.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2414–2419, November, 2004. 相似文献
993.
Hosoya K Hira N Watabe Y Tanaka N Kubo T Kaya K 《Analytical and bioanalytical chemistry》2004,380(2):343-345
Thiacalix[4]arene (5,11,17,23-tetra-tert-butyl-25,26,27,28-tetrahydroxy-2,8,14,20-tetrathiacalix[4]arene) is an amphiphilic molecule comprising four p-tert-butylphenol-like groups ortho-linked by single sulfur atoms. This molecule has a high electron density area owing to the close proximity of the hydroxyl groups and sulfur atoms. We studied the applicability of this interesting compound as a selector for high-performance liquid chromatography (HPLC) thereby presumably exploiting this feature. Firstly, uniformly sized polymer particles were prepared by using a multi-step swelling and polymerization method with ethylene glycol dimethacrylate (EDMA) as a cross-linker. Methacrylic acid (MAA) was introduced onto the surface of the resulting polymer particles through a new modification method. Thiacalix[4]arene was chemically bonded through the MAA group by using 1,4-dibromobutane as a spacer to reduce steric hindrance around the MAA and the polymer particle itself. The performance of the prepared polymer-based thiacalix[4]arene-modified stationary phase was evaluated with HPLC. Specific chromatographic retention behavior was observed for catechol relative to positional isomers of xylene, cresol, and benzene-diol. Catecholamine and catechol showed specific chromatographic retention behavior. 相似文献
994.
Starting from the para‐phenylenediamine derivative HN(SiMe3)‐C6H4‐NH(SiMe3), a lithiation and subsequent borylation give [(MeO)2B]N(SiMe3)‐C6H4‐N(SiMe3)[B(OMe)2] ( 1 ), the hydridation of which yields Li2[(H3B)N(SiMe3)‐C6H4‐N(SiMe3)(BH3)] ( 2 ). Applying ZrCl4 upon 2 initiates a condensation to give the title compound [‐N(SiMe3)‐p‐C6H4‐N(SiMe3)‐BH‐]2, a hetero[3, 3]paracyclophane with two N‐B‐N chains that connect the para‐phenylene units. The product 3 crystallizes in the orthorhombic space group P212121. 相似文献
995.
Summary: A new calix[4]arene‐based periodic mesoporous organosilica has been synthesized using tetraethoxysilane (TEOS) and a calix[4]arene‐based silane monomer as the precursors and cetyltrimethylammonium bromide (CTAB) surfactant as the structure‐directing template, and is shown to be capable of visual detection and entrapment of NO2.
996.
Gareth J. Rowlands Author Vitae 《Tetrahedron》2010,66(9):1593-501
997.
Won Hee Kim Jin-Ah Kang Jin-Ah Kim Pusoon Chun Chong-Kyo Lee Hyung Ryong Moon 《Tetrahedron》2010,66(9):1706-5156
The first synthesis of 2′-oxabicyclo[3.1.0]hexyl nucleosides, a novel class of bicyclonucleosides, with a north conformation was successfully accomplished starting from (S)-epichlorohydrin via a tandem alkylation-lactonization, a less steric hindrance-dependent silylation in equilibrium and a coupling reaction with nucleobases under Vorbruggen conditions. Addition of acetic acid prevented a benzoyl group from migrating during desilylation with TBAF. 1H NMR and X-ray crystallographic analysis indicated that the anomeric effect worked on the β-2′-oxabicyclo[3.1.0]hexyl nucleosides. 相似文献
998.
Sun Pil Park 《Tetrahedron》2010,66(19):3490-3498
A simple method for synthesizing several 6H-pyrrolo[1,2-c][1,2,3]triazole derivatives having a methoxycarbonyl or an acetyl group at C-5 position and 7,8-dihydro-4H-[1,2,3]triazolo[1,5-a]indol-5(6H)-ones via an intramolecular 1,3-dipolar cycloaddition reaction of azido enynes, which were readily obtained from the Morita-Baylis-Hillman acetates of propargyl aldehydes with sodium azide, has been developed. 相似文献
999.
The ozonation of four bornene derivatives, prepared from (R)-(+)-pulegone, which possess a particularly hindered double bond, led to the formation of unexpected products depending on the nature of the solvent. The formation of the corresponding epoxides, ketones with the same skeleton, various lactones and even an allyl alcohol and an allyl chloride (allylic functionalisation) was observed. In two cases, products presenting a pulegone modified skeleton resulting from a Wagner-Meerwein rearrangement were obtained. The structure of three products was confirmed by crystallographic X-ray analysis. Mechanisms taking into account the rigid and congested structure of the reactants explain these results. The most striking steps were backed up by theoretical calculations. 相似文献
1000.
Bicyclo[3.2.1]octan-8-ones have been prepared from a tandem Michael-Henry reaction between cyclohexane-1,2-diones and nitroalkenes using a quinine-derived thiourea as the catalyst. Although four stereogenic centers were created during the reaction, only two diastereomers were obtained in good diastereoselectivity and high enantioselectivity (92-99% ee). When 3-methylcyclohexane-1,2-dione (R1=Me) was used as the substrate, only the regioisomeric product of the corresponding thermodynamic enolate was obtained. 相似文献