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11.
Indoles undergo smooth alkylation with cyclopropyl ketones in the presence of the CeCl3·7H2O/LiI reagent system in refluxing acetonitrile under neutral conditions to produce the corresponding C-3 substituted indole derivatives in good to high yields and with high selectivity. The use of CeCl3·7H2O/LiI makes this method simple, convenient, and cost-effective. 相似文献
12.
Tsunehisa Hirashita Yousuke Hayashi Kazuma Mitsui Shuki Araki 《Tetrahedron letters》2004,45(16):3225-3228
Vinyl and methylindium ate complexes (indates) were prepared and both the tendency of immigration and regioselectivity toward cinnamyl bromide were investigated. The vinyl group was more preferably transferred than the Me group, giving a regioisomeric mixture of SN2 and SN2′ products. The ratio of SN2/SN2′ selectivity can be controlled by solvents; in the presence of polar solvents, such as N-butylpyrrolidone (NBP) and THF, the SN2′ product was mainly obtained, whereas the SN2 product was selectively prepared in solutions containing hexane. The vinylindium compound, generated by the reaction of allylic-type diindium reagents with imine, was also converted to the corresponding vinyl indate, which was allowed to react with allyl chloride to give a three-component coupling product. 相似文献
13.
O. A. Luk'yanov I. A. Savost'yanova V. P. Gorelik N. I. Shlykova V. A. Tartakovskii 《Russian Chemical Bulletin》1992,41(8):1395-1399
Silver and mercury salts of nitro compounds react with bromo- or chloroadamantanes with the formation of products of C- and/or O-alkylation, the ratio of which depends on the structure of the initial reactants. The direct experimental evidence of nitronic esters to be isomerized into nitro derivatives and of their role as intermediates in the formation of the nitro derivatives in the alkylation of nitro compounds has been presented for the first time.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. Translated from Izvestiva Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1798–1803, August, 1992. 相似文献
14.
Naoya Inazumi Shunzo Yamamoto Yoshimi Sueishi 《Journal of inclusion phenomena and macrocyclic chemistry》2007,59(1-2):33-39
The inclusion complexation of p-sulfonatocalix[6]arene (Calix-S6) with three kinds of phenothiazine dyes was studied spectrophotometrically in a mixture
of a room-temperature ionic liquid [bmim]BF4 (1-butyl-3-methylimidazolium tetrafluoroborate) and ethanol. We have determined the association constants of Calix-S6 with
phenothiazine dyes under external static pressure up to 767 bar in the [bmim]BF4-ethanol and alcohol-water mixtures. With increasing external pressure, the inclusion equilibrium in the alcohol-water mixtures
was shifted to the dissociation side. Conversely, the inclusion equilibrium of methylene blue (MB) and azure A (AA) in the
ionic liquid mixture was shifted to the association side. From the analysis of the pressure effects, the reaction volumes
ΔV for inclusion complexation were estimated as −7 to 9 cm3 mol−1 in the [bmim]BF4-ethanol mixture and 20–32 cm3 mol−1 in the alcohol-water mixtures. Based on the results, we have suggested that there is a competing complexation between the
included dye and [bmim]BF4 molecules in the ionic liquid. 相似文献
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Anthony P. Panarello 《Tetrahedron letters》2005,46(8):1353-1356
Chiral ansa-ethylene-bis(indenyl)-metal complexes, EBI-MX2, are useful pre-catalysts for a wide variety of reactions, including hydrogenations, hydrosilylations, and polymerization reactions. In order to immobilize these complexes onto heterogeneous supports, a new methodology was developed to introduce functional anchors to the ethylene-bis(indenyl) ligand, EBI. This was accomplished by selective alkylation of indene to form toluene-4-sulfonic acid 2-(3H-inden-1-yl)-ethyl ester, which was then used to alkylate 6-bromoindene. The selective introduction of an aryl bromide then undergoes coupling reactions with aryl borates via the Suzuki coupling to efficiently introduce an alkenyl or alcohol, functional anchor in a simple four step synthesis. 相似文献