A 48 Aminomethyl bi- and terpyridines as luminescent probes for Zn2+ ions [Electronic resource] / V. N. Kozhevnikov, O. V. Shabunina, A. R. Sharifullina, V. L. Rusinov, O. N. Chupakhin, B. Koenig // Mendeleev Communications. - 2005. - Vol. 15, № 1. - P8-9 Рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: 2,2'-Bi- and 2,2':6',2"-terpyridines, bearing aminomethyl and aryl substituents, show a significant increase in emission intensity and bathochromic emission wavelength change upon the addition of zinc ions in aqueous solution, and they can be used as luminescent probes for zinc ions in physiological media. \\\\Expert2\\nbo\\Mendeleev Communications\\2005, v.15, p.8.pdf |
S 98 Synthesis of 8-R-9c-alkyl-1-aryl-2-benzyl-1-hydroxy-1,2,9b,9c-tetrahydro-5-oxa-2-aza-cyclopenta[2,3]cyclopropa[1,2-a]naphthalene-3,4-diones and reaction thereof with acetic anhydride [Text] / V. V. Shchepin, P. S. Silaichev, A. R. Racitin, M. I. Kodess // Tetrahedron Letters. - 2006. - Vol. 47, № 4. - P557-560 Рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: The reaction of zinc enolates synthesized from 1-aryl-2,2-dibromoalkanones and zinc with 6-R-2-oxochromene-3-carboxylic acid N-benzylamide affords 8-R-9c-alkyl-1-aryl-2-benzyl-1-hydroxy-1,2,9b,9c-tetrahydro-5-oxa-2-aza-cyclopenta[2,3]cyclopropa[1,2-a]naphthalene-3,4-diones. Acylation of these compounds is accompanied by an unexpected rearrangement producing a sole geometrical isomer of 4?-alkyl-5?-aryl-1?-benzyl-3,4,2?,3?-tetrahydro-2,2?-dioxospiro[chroman-3,3?-pyrrol]-4-yl acetates \\\\Expert2\\nbo\\Tetrahedron Letters\\2006, v. 47, p.557.pdf |
5-Aryl-2,2-bipyridines as tunable fluorophores [Text] / D. N. Kozhevnikov, O. V. Shabunina, D. S. Kopchuk, P. A. Slepukhin, V. N. Kozhevnikov // Tetrahedron Letters. - 2006. - Vol. 47, № 39. - P7025-7029 Рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: Readily available 5-aryl-2,2?-bipyridines and their derivatives are a unique family of fine-tunable chromophores, where changes in the substitution patterns, solvation and coordination are translated into dramatic spectral changes. They exhibit sensitive and selective response to zinc ions with dramatic increases in emission intensity or significant red-shifts of emission maxima???? \\\\Expert2\\nbo\\Tetrahedron Letters\\2006, v. 47, p.7025.pdf |
S 98 Synthesis of novel perfluoroalkyl-containing polyethers [Text] / D. N. Bazhin, T. I. Gorbunova, A. Ya. Zapevalov, V. I. Saloutin // Journal of Fluorine Chemistry. - 2009. - Vol. 130, № 4. - P438-443 Рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: The synthesis of iodo(perfluoroalkyl)epoxides by radical addition of perfluoroalkyl iodides to allyl glycidyl ether and 1,2-epoxydec-9-ene is described. Dehydroiodination of additional products upon treatment with 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) gives unsaturated products. The use of Bu3SnH/Bz2O2 as a reduction reagent of iodo(perfluoroalkyl)allyl glycidyl ethers allows to save oxirane ring. Cationic polymerization of saturated or functional (with iodine or double bond) fluoroalkyl oxiranes under action of catalytic amount of BF3.Et2O proceeds only on epoxide group. In case of poly(9-iod-10-(perfluoroalkyl)-1,2-epoxyalkane) iodine atoms are removed by standard zinc reduction \\\\Expert2\\nbo\\Journal of Fluorine Chemistry\\2009, V. 130, P. 438.pdf |
П 53 Получение нитевидных кристаллов ZNCO2O4 со структурой шпинели из оксалата цинка-кобальта = Preparation of ZnCo2O4 Spinel Whiskers from Zinc Cobalt Oxalate [] / Г. В. Базуев, О. И. Гырдасова, И. Г. Григоров, О. В. Корякова // Неорганические материалы. - 2005. - Т. 41, № 3. - С. 348-352. - Библиогр.: с. 352 (10 назв.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: Разработана методика получения шпинели ZnCo2O4 в виде нитевидных кристаллов (вискеров) диа-метром 2-5 и длиной до 50 мкм, сохраняющей свой состав и форму до 800°С. Методика основана на разложении двойных оксалатов состава Zn1/3Co2/3C2O4 2Н2О на воздухе. Результаты исследований подтверждены методами химического и рентгенофазового анализов, ИК- и растровой электронной микроскопией |
P 51 Petrological model of formation of giant ore deposits [Text] / A. A. Marakushev, N. A. Paneyakh, V. L. Rusinov, N. N. Pertsev, I. A. Zotov // Geology of Ore Deposits. - 1998. - Vol. 40, № 3. - P211-227. - Bibliogr. : p. 227 (46 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): PETROLOGICAL MODEL -- MODELLING -- ORE -- ORE DEPOSITS Аннотация: The available data on the giant ore deposits of chromium (Kempirsai in the Urals), platinum-group metals (Bushveld in Africa), platinum-bearing copper-nickel ores (Talnakh in the Noril'sk district, northern part of the Siberian Platform), zinc-copper (massive sulfide) ores (Gai, Sibai, and Uchaly) and apatite deposits (Khibiny, the Kola Peninsula) is summarized. The giant sizes of the deposits are caused by extraordinary ore-forming processes directly associated with the highly extensive petrogenetic processes. These processes resulted in the formation of peculiar dunites in the hyperbasite complexes (chromite ores), agpaitic urtites in alkaline associations (apatite deposits), development of low-sulfide horizons and hortonolite dunites in the basite-hyperbasite layered intrusions (platinum-group metal deposits), specific processes of transmagmatic sulfurization of the iron-rich igneous differentiates (Cu-Ni sulfide and massif sulfide ores), and processes of magmatic replacement of hyperbasites that cause the alkaline agpaitic affinity of magmatism. This agpaitic tendency increases the solubility of carbon-bearing fluid components (CO2, CH4, etc.) in magma and leads to the concentration of ore metals, which form chloride-carbonate and hydrocarbon migrating compounds in the transmagmatic fluids. Some mineralogical-petrological prospecting criteria are deduced on the basis of genetic models of giant ore deposits. |
R 30 Reactions of zinc enolates derived from 1-aryl-2,2-di-bromoalkanones with 2-acyl-3H-benzo[f]chromen-3-ones, 6-bromo-2-oxochromene-3-carboxamides, and 3-oxo-3H-benzo-[f]chromene-2-carboxamides [Electronic resource] / V. V. Shchepin, M. M. Kalyuzhnyi, P. S. Silaichev, M. A. Ezhikova, M. I. Kodess // Russian Journal of Organic Chemistry (Translation of Zhurnal Organicheskoi Khimii). - 2004. - Vol. 40, № 9. - P1353-1358 Рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: Zinc enolates derived from substituted 1-aryl-2,2-dibromoalkanones reacted with 2-acyl-3H-benzo-[f]chromen-3-ones to give 1-alkyl-1-aroyl-1a-acyl-1a, 9c-dihydro-1H-3-oxacyclopropa[c]phenanthren-2-ones which were formed as a single stereoisomer. Reactions of the same zinc enolates with 6-bromo-2-oxo-chromene-3-carboxamides (piperidides and morpholides) afforded 1-aroyl-6-bromo-1-alkyl-1a-piperidino-(morpholino)carbonyl-1a,7b-dihydrocyclopropa[c]chromen-2-ones with high stereoselectivity. Likewise, 1-benzoyl-1-methyl-1a-morpholinocarbonyl-1a, 9c-dihydro-1H-3-oxacyclopropa[c]phenanthren-2-one was obtained by reac-tion with 3-oxo-3H-benzo[f]chromene-2-carboxylic acid morpholide \\\\Expert2\\nbo\\Russian Journal of Organic Chemistry\\2004, 40 (9), 1353.pdf |
R 30 Reaction of organozinc reagents formed in reaction of dibromomalonic acid dialkyl esters and zinc, with 2-arylmethylenemalonic acid dinitriles and 3-aryl-2-cyanopropenoic acid methyl esters [Electronic resource] / V. V. Shchepin, Yu. G. Stepanyan, P. S. Silaichev, M. I. Kodess // Russian Journal of General Chemistry. - 2006. - Vol. 76, № 12. - P1919-1921 Рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: Organozinc compounds, obtained from dibromomalonic acid dialkyl esters and zinc, react with 2-arylmethylmalonic acid dinitriles and 3-aryl-2-cyanopropenoic acid methyl esters forming 3-aryl-2,2-dicyanocyclopropane-1,1-dicarboxylic acid dialkyl esters and 3-aryl-2-cyanocyclopropane-1,1,2-tricarboxylic acid trimethyl esters \\\\Expert2\\nbo\\Russian Journal of General Chemistry\\2006, V. 76, N 12, p.1919.pdf |
R 30 Reactions of zinc enolates derived from 1-aryl-2-bromo-2-phenylethanone and 2-bromoindan-1-one with alkyl 2-oxochromene-and 6-bromo-2-oxochromene-3-carboxylates [Electronic resource] / V. V. Shchepin, A. E. Korzun, M. I. Vakhrin, P. S. Silaichev, M. A. Ezhikova, M. I. Kodess // Russian Journal of General Chemistry. - 2006. - Vol. 76, № 5. - P777-780 Рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: Zinc enolates derived from 1-aryl-2-bromo-2-phenylethanone react with alkyl 2-oxochromene-3-carboxylates and methyl 6-bromo-2-oxochromene-3-carboxylate to give, respectively, alkyl 4-(2-aryl-2-oxo-1-phenylethyl)-2-oxochroman-3-carboxylates and methyl 6-bromo-4-(2-aryl-2-oxo-1-phenylethyl)-2-oxochroman-3-carboxylate as a single stereoisomer. Zinc enolates derived from 2-bromoindan-1-one react with alkyl 2-oxochromene-3-carboxylates to give alkyl 2-oxo-4-(1-oxoindan-2-yl)chroman-3-carboxylates as a single stereoisomer \\\\Expert2\\nbo\\Russian Journal of General Chemistry\\2006, V. 76, N 5, p.777.pdf |
C 98 Cyclopropanation of N-Substituted 2-Oxochromene- and 6-Bromo-2-oxochromene-3-carboxamides with Zinc Enolates Derived from 1-Aryl-2,2-dibromoalkanones [Electronic resource] / V. V. Shchepin, P. S. Silaichev, R. V. Shchepin, M. A. Ezhikova, M. I. Kodess // Russian Journal of Organic Chemistry (Translation of Zhurnal Organicheskoi Khimii). - 2005. - Vol. 41, № 4. - P527-534 Рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: Zinc enolates derived from 1-aryl-2,2-dibromoalkanones react with N-cyclohexyl-2-oxochromene-3-carboxamides to give N-cyclohexyl-1-alkyl-1-aroyl-2-oxo-1a,7b-dihydrocyclopropa[c]chromene-1a-carboxamides mainly as cis isomers with respect to the substituents in positions 1 and 1a. Reactions of the same zinc enolates with N-benzyl-2-oxochromene-3-carboxamide and N-benzyl-6-bromo-2-oxochromene-3-carboxamide lead to formation of 1-aryl-2-benzyl- and 1-aryl-2-benzyl-6-bromo-1-hydroxy-9c-alkyl-1,2,9b,9c-tetrahydro-5-oxa-2-azacyclopenta[2,3]cyclopropa[1,2-a]naphthalene-3,4-diones. The reaction of zinc enolates with N-aryl-2-oxochromene-3-carboxamides in a weakly polar solvent (diethyl ether or ethyl acetate) affords mixtures of cis-N-aryl-1-aroyl-1-alkyl-2-oxo-1a,7b-dihydrocyclopropa[c]chromene-1a-carboxamides and their cyclic isomers, 9c-alkyl-1,2-diaryl-1-hydroxy-1,2,9b,9c-tetrahydro-5-oxa-2-azacyclopenta[2,3]cyclopropa[1,2-a]naphthalene-3,4-diones, the latter prevailing. N-Substituted 1-alkyl-1-aroyl-2-oxo-1a,7b-dihydrocyclopropa[c]chromene-1a-carboxamides in which the aroyl group on C1 and the carboxamide group on C1a are arranged trans are formed by reactions of zinc enolates with the corresponding 2-oxochromene-3-carboxamides in the presence of hexamethylphosphoric triamide \\\\Expert2\\nbo\\Russian Journal of Organic Chemistry\\2005, 41 (4), 527.pdf |
S 53 Shchepin, V. V. Reaction of zinc enolates prepared from 2,2-dibromoindan-1-one or 2,2-dibromo-1-tetralone and zinc with 2-oxochromen-3-carboxylic acid derivatives [Electronic resource] / V. V. Shchepin // Russian Journal of Organic Chemistry (Translation of Zhurnal Organicheskoi Khimii). - 2007. - Vol. 43, № 10. - P1441-1445 Рубрики: ХИМИЧЕСКИЕ НАУКИ \\\\Expert2\\nbo\\Russian Journal of Organic Chemistry\\2007, 43 (10), 1441.pdf |
C 98 Cyclopropanation of 2-arylmethylidenemalononitriles, alkyl 3-aryl-2-cyanoprop-2-enoates, and N-substituted 3-aryl-2-cyanoprop-2-enamides with bromine-containing zinc enolates [Electronic resource] / V. V. Shchepin, Yu. G. Stepanyan, P. S. Silaichev, M. A. Ezhikova, M. I. Kodess // Russian Journal of Organic Chemistry (Translation of Zhurnal Organicheskoi Khimii). - 2007. - Vol. 43, № 7. - P1002-1007 Рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: Zinc enolates derived from 2,2-dibromoindan-1-one and 2,2-dibromo-1,2,3,4-tetrahydronaphthalen-1-one reacted with 2-arylmethylidenemalononitriles, alkyl 3-aryl-2-cyanoprop-2-enoates, and N-substituted 3-aryl-2-cyanoprop-2-enamides to give, respectively, 3-aryl-1?-oxo-1?,3?-dihydrospiro[cyclopropane-1,2?-indene]-2-2-dicarbonitriles, 3-aryl-1?-oxo-3?,4?-dihydro-1?H-spiro[cyclopropane-1,2?-naphthalene]-2,2-dicarbonitriles, alkyl 3-aryl-2-cyano-1?-oxo-1?,3?-dihydrospiro[cyclopropane-1,2?-indene]-2-carboxylates, alkyl 3-aryl-2-cyano-1?-oxo-3?,4?-dihydro-1?H-spiro[cyclopropane-1,2?-naphthalene]-2-carboxylates, and N-substituted 3-aryl-2-cyanol-1?-oxo-3?,4?-dihydro-1?H-spiro[cyclopropane-1,2?-naphthalene]-2-carboxamides as a single diastereoisomer. The stereoconfiguration of the products was determined by 1H and 13C NMR spectroscopy \\\\Expert2\\nbo\\Russian Journal of Organic Chemistry\\2007, 43 (7), 1002.pdf |
R 30 Reaction of organozinc reagents prepared from bromomalonic acid esters and zinc with 3-aryl-2-cyanopropenoic acid primary amides [Electronic resource] / V. V. Shchepin, P. S. Silaichev, Yu. G. Stepanyan, N. Yu. Russkikh, M. I. Vakhrin, M. A. Ezhikova, M. I. Kodess // Russian Journal of Organic Chemistry (Translation of Zhurnal Organicheskoi Khimii). - 2006. - Vol. 42, № 11. - P1625-1629 Рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: Organozinc compounds prepared from bromomalonic acid esters and zinc react with 3-aryl-2-cyanopropenoic acid primary amides giving a single diastereomer of the corresponding 1-R?-4-aryl-2,6-dioxo-5-cyanopiperidine-3-carboxylic acid esters, or 3-R?-6-aryl-2,4-dioxo-5-cyano-3-azabicyclo[3.1.0]hexene-1-carboxylic acid esters \\\\Expert2\\nbo\\Russian Journal of Organic Chemistry\\2006, 42 (11), 1625.pdf |
R 30 Reactions of zinc enolates derived from 1-aryl-2-bromo-alkanones and 1-aryl-2-bromo-2-phenylethanone with 3-aroyl-6-bromochromen-2-ones and 2-benzoylbenzo[f]chromen-3-one [Electronic resource] / V. V. Shchepin, A. E. Korzun, M. I. Vakhrin, P. S. Silaichev, M. A. Ezhikova, M. I. Kodess // Russian Journal of Organic Chemistry (Translation of Zhurnal Organicheskoi Khimii). - 2006. - Vol. 42, № 9. - P1344-1347 Рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: 3-Aroyl-6-bromochromen-2-ones and 2-benzoylbenzo[f]chromen-3-one reacted with zinc enolates derived from 1-aryl-2-bromoalkanones and 1-aryl-2-bromo-2-phenylethanone to give, respectively, 4-(1-alkyl-2-aryl-2-oxoethyl)-3-aroyl-6-bromochroman-2-ones and 1-(2-aroyl-1-methyl-2-oxoethyl)-2-benzoyl-1,2-dihydrobenzo[f]chromen-3-ones as a single stereoisomer. Treatment with acetic anhydride of the intermediate product obtained from 3-benzoyl-6-bromochromen-2-one and [1-(4-chlorophenyl)-2-phenylethen-1-yloxy]-zinc(II) bromide resulted in the formation of 3-(1-acetoxy-1-phenylmethylidene)-6-bromo-4-[2-(4-chlorophenyl)-2-oxo-1-phenylethyl]chroman-2-one \\\\Expert2\\nbo\\Russian Journal of Organic Chemistry\\2006, 42 (9), 1344.pdf |
R 30 Reaction of N-substituted 2-oxochromen-3-carboxamides with bromoderivatives of zinc enolates prepared from alkyl 2,2-dialkyl-4,4-dibromo-3-oxoalkanoates and zinc [Electronic resource] / V. V. Shchepin, P. S. Silaichev, N. Yu. Russkikh, M. I. Vahrin, M. I. Kodess // Russian Journal of Organic Chemistry (Translation of Zhurnal Organicheskoi Khimii). - 2006. - Vol. 42, № 8. - P1157-1163 Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): ZINC ENOLATES -- CARBOXAMIDES -- E-POSITION Аннотация: Zinc enolates obtained from ethyl 2,2-dialkyl-4,4-dibromo-3-oxobutanoates and zinc react with N-substituted 2-oxochromen-3-carboxamides forming ethyl 3-(1a-(R3-carbamoyl)-2-oxo-1a,7b-dihydrocyclopropa[c]chromen-1-yl)-2,2-dialkyl-3-oxopropanoate isomer with a Z-position of methine hydrogens. Zinc enolates prepared from alkyl 2,2-dialkyl-4,4-dibromo-3-oxopentanoates and-hexanoates and zinc react with N-substituted 2-oxochromen-3-carboxamides to give rise to esters of 3-(1-alkyl-1a-(R3-carbamoyl)-2-oxo-1a,7b-dihydrocyclopropa-[c]chromen-1-yl)-2,2-dialkyl-3-oxopropanoic acid as isomers with the E-position of the methine proton and the alkyl substituent. The reaction carried out in the presence of small quantities of THF and HMPA leads to the formation of 9c-alkyl-2-R3-9b,9c-dihydro-5-oxa-2-azacyclopenta[2,3]-cyclopropa[1,2-a]naphthalene-1,3,4-triones. Zinc enolates from alkyl 2,2-dialkyl-4,4-dibromo-3-oxopentanoates and-hexanoates and zinc with the secondary amides of 2-oxochromen-3-carboxylic acid form alkyl 3-(2-oxo-1a-(piperidinocarbonyl)-and 3-(6-R1-1a-(morpholinocarbonyl)-2-oxo-1a,7b-dihydrocyclopropa[c]chromen-1-yl)-2,2-R2,R2-3-oxopropanoates as single geometrical isomers \\\\Expert2\\nbo\\Russian Journal of Organic Chemistry\\2006, 42 (8), 1157.pdf |
R 30 Reaction of alkyl 5,5-dimethyl-2-oxo-2,5-dihydrofuran-3-carboxylates with zinc enolates prepared from zinc and 1-arul-2-bromo-2-phenylethanones, 2 bromoindanone, and 2-bromo-6-methyltetralone [Electronic resource] / V. V. Shchepin, A. E. Korzun, M. I. Vakhrin, P. S. Silaichev, M. A. Ezhikova, M. I. Kodess // Russian Journal of Organic Chemistry (Translation of Zhurnal Organicheskoi Khimii). - 2006. - Vol. 42, № 8. - P1169-1173 Рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: Alkyl 5,5-dimethyl-2-oxo-2,5-dihydrofuran-3-carboxylates react with zinc enolates prepared from 1-aryl-2-bromo-2-phenylethanones, 2-bromo indanone, 2-bromo-6-methyltetralone and zinc with formation of ethyl 4-(2-aryl-2-oxo-1-phenyl-ethyl)-5,5-dimethyl-2-oxotetrahydrofuran-3-carboxylates, alkyl 5,5-dimethyl-2-oxo-4-(1-oxoindan-2-yl)tetrahydrofuran-3-carboxylates, and ethyl 5,5-dimethyl-4-(6-methyl-1-oxo-1,2,3,4-tetrahydronaphthalen-2-yl)-2-oxotetrahydrofuran-3-carboxylates respectively, mainly as single diastereomers \\\\Expert2\\nbo\\Russian Journal of Organic Chemistry\\2006, 42 (8), 1169.pdf |
C 98 Cyclopropanation of N-substituted 3-aryl-2-cyanoprop-2-enamides and derivatives of 5,5-Dimethyl-2-oxo-2,5-dihydrofuran-3-carboxylic acid and 2-oxochromene-3-carboxylic acid with bromine-containing zinc enolates [Electronic resource] / V. V. Shchepin, P. S. Silaichev, Yu. G. Stepanyan, M. M. Kalyuzhnyi, N. Yu. Russkikh, M. I. Kodess // Russian Journal of Organic Chemistry (Translation of Zhurnal Organicheskoi Khimii). - 2006. - Vol. 42, № 7. - P973-980 Рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: Zinc enolates derived from 1-aryl-2,2-dibromoalkanones react with N-substituted 3-aryl-2-cyanoprop-2-enamides and 5,5-dimethyl-2-oxo-2,5-dihydrofuran-3-carboxylic and 2-oxochromene-3-carboxylic acid derivatives to give, respectively, N-substituted 2-alkyl-3-aryl-2-aroyl-1-cyanocyclopropane-1-carboxamides, 6-(4-bromobenzoyl)-4,4,6-trimethyl-2-oxo-3-oxabicyclo[3.1.0]hexane-1-carboxylic acid ethyl ester and morpholide, and 1-alkyl-1-aroyl-2-oxo-1a,7b-dihydrocyclopropla[c]chromene-1a-carboxylic acids as a single geometric isomer. Treatment of 1-alkyl-1-aroyl-2-oxo-1a,7b-dihydrocyclopropa[c]chromene-1a-carboxylic acids with carboxylic acid anhydrides leads to the formation of the corresponding 9c-alkyl-1-aryl-3,4-dioxo-9b,9c-dihydro-2,5-dioxacyclopenta[2,3]cyclopropa[1,2-a]naphthalen-1-yl carboxylates \\\\Expert2\\nbo\\Russian Journal of Organic Chemistry\\2006, 42 (7), 973.pdf |
S 98 Synthesis, Structure, and Keto-Enol Tautomerism of 3-R1-5,5-R2,R2-6-R3-2,3,5,6-Tetrahydropyran-2,4-diones [Electronic resource] / V. V. Shchepin, M. I. Kodess, Yu. Kh. Sazhneva, N. Yu. Russkikh // Russian Journal of General Chemistry. - 2005. - Vol. 75, № 10. - P1622-1627 Рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: Ethyl esters of 2,4-dibromo-2-R1-4-R2-3-oxopentanoic and -hexanoic acids react with zinc and aliphatic or aromatic aldehydes under the conditions of the Reformatskii reaction to give 3-R1-5,5-R2, R2-6-R3-2,3,5,6-tetrahydropyran-2,4-diones, which are obtained in three forms: keto, enol with enolization of the keto group, and enol with enolization of the ester group. The keto form is isolated by crystallization from a mixture of CCl4 and petroleum ether; the first enol form, from MeOH, EtOH, and polar aprotic solvents; and the second enol form, from CHCl3. The second enol form is oxidized in DMSO to form a keto compound containing a hydroxy group at the 3-position of the heteroring \\\\Expert2\\nbo\\Russian Journal of General Chemistry\\2005, V. 75, N 10, p.1622.pdf |
W 20 Wall Rock Metasomatism and Formation Conditions of the Silver-Polymetallic Bol'shoi Kanimansur Deposit (Tadjikistan) [Text] / O. V. Rusinova, V. L. Rusinov, E. D. Syngaevskii , L. I. Bochek, M. I. Lapina, Yu. V. Vasyuta // Geology of Ore Deposits. - 2001. - Vol. 43, № 5. - P386-405. - Bibliogr. : p. 405 (20 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): SILVER-POLYMETALLIC DEPOSIT -- CARBON -- METASOMATIC TRANSFORMATIONS -- REGIONAL MAGMATISM Аннотация: Products of the hydrothermal alteration of rocks and vertical zonality at the Kanimansur silver-polymetallic deposit (Tadjikistan) have been studied. On the basis of these studies, physicocochemical conditions of metasomatism and ore formation were reviewed. Condensed carbonaceous matter in wall rock metasomatites and ores were found and carbon isotopic composition of this carbonaceous matter and composition of gases in open pores in rocks of the deposit were analyzed. As a result of geological observations, analysis of mineral parageneses, compositions of minerals, and chemistry of wall rock alteration, the following four stages of the hydrothermal process were distinguished: autometasomatic, propylitic, preore chlorite-sericite, and synore. Mineral geothermometers were used to estimate the temperatures of metasomatism, which varied within the range 200-250°C for all stages except for the autometasomatic stage (450-500°C). The formation of unhydrated light micas, quartz, and highly ferruginuous chlorites was related to acid preore metasomatism. The stability of these chlorites testifies to a slight increase in the acidity of solutions during the preore stage (pH not less than 3.5). The wall rock metasomatites and sulfide ores are characterized by a relatively rare occurrence of pyrite due to a low activity of the sulfide sulfur during hydrothermal alterations (logaS2 = -7...-10). The low activity of the sulfide sulfur is confirmed by the fact that iron is tied in a highly ferruginuous chlorite. At upper ore levels, even zinc is tied in chlorite. This testifies to a much greater aS2 /aO2 value. Judging by the participation of carbonaceous matter in the process, ore components were deposited due to a local increase in the alkalinity at the ore-forming stage and oxidation of reduced fluids. The established features of metasomatic transformations, are related to particulars of the regional magmatism.???? |
K 42 Khomutov, O. G. Selective reduction of derivatives of fluorinated beta-diketones [Text] / O. G. Khomutov, V. I. Filyakova, K. I. Pashkevich // Journal of Fluorine Chemistry. - 1992. - Vol. 58, № 2-3. - P351 Рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: The reduction of fluorinated ?-diketones (DK) is known to give ?-diols [G. Swalens, M. Anteunis and D. Tavernier, Bull. Soc. Chim. Belg., 79 (1970) 441–450] and ?-hydroxyketones (HK) II [A.L. Henne and P.E. Hinkamp, J. Am. Chem. Soc., 76 (1954) 5147]. We have established that the lithium salts (Ia) as well as chelate compounds of DK with zinc (Ib) and aluminium (Ic) undergo selective reduction with LiAlh4 to HK III. Salts (Id) and chelate compounds (If) are not reduced under the same conditions |