- Koch carbonylation using silver trifluoromethanesulfonate
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Koch carbonylation was carried out using silver trifluoromethanesulfonate (AgOTf). Tertiary alcohols were transformed into the corresponding carboxylic acids in good yield under carbon monoxide atmosphere (5 MPa: initial pressure) at 150°C. It can be assumed that under these reaction conditions, a strong acid, in which a silver(I) cation participates, would be generated from AgOTf.
- Mori, Hajime,Mori, Aya,Xu, Qiang,Souma, Yoshie
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- Auxiliary-Directed C(sp3)?H Arylation by Synergistic Photoredox and Palladium Catalysis
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Herein we describe the auxiliary-directed arylation of unactivated C(sp3)?H bonds with aryldiazonium salts, which proceeds under synergistic photoredox and palladium catalysis. The site-selective arylation of aliphatic amides with α-quaternary centres is achieved with high selectivity for β-methyl C(sp3)?H bonds. This operationally simple method is compatible with carbocyclic amides, a range of aryldiazonium salts and proceeds at ambient conditions.
- Czyz, Milena L.,Lupton, David W.,Polyzos, Anastasios
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- CATALYTIC CARBOXYLATION OF ACTIVATED ALKANES AND/OR OLEFINS
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The present invention relates to a method of reacting starting materials with an activating group, namely alkanes carrying a leaving group and/or olefins, with carbon dioxide under transition metal catalysis to give carboxyl group-containing products. It is a special feature of the method of the present invention that the carboxylation predominantly takes place at a preferred position of the molecule irrespective of the position of the activating group. The carboxylation position is either an aliphatic terminus of the molecule or it is a carbon atom adjacent to a carbon carrying an electron withdrawing group. The course of the reaction can be controlled by appropriately choosing the reaction conditions to yield the desired regioisomer.
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Page/Page column 57; 62; 63; 65; 66
(2018/02/28)
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- Process for synthesis of tertiary carboxylic acids and the esters thereof
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The present invention provides a process for synthesizing tertiary carboxylic acids or the esters thereof having one or two more carbon atoms than the raw material has, comprising reacting in a strong acid (e.g., sulfuric acid, sulfuric acid-phosphoric acid, hydrogen fluoride, fluorosulfuric acid, boron trifluoride.water complex and trifluoromethanesulfonic acid) a raw material compound (i.e., olefin, alcohol, diene, diol or saturated hydrocarbon) with carbon monoxide in the presence of a specific metal carbonyl catalyst (i.e., platinum carbonyl catalyst, palladium carbonyl catalyst and gold dicarbonyl catalyst). The metal carbonyl catalyst is formed by reacting in a strong acid at least one specific metal compounds (e.g., platinum compound such as platinum (II, IV) oxide, platinum (II, IV) hydroxide, a platinum powder, etc.; palladium compound such as palladium (II, III, IV) oxide, palladium (II) hydroxide, palladium (II) sulfate, palladium (II) carboxylate, a palladium powder, etc.; and gold compound such as gold (I, III) oxide, gold (I, III) hydroxide, a gold powder, etc.) with carbon monoxide.
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- Novel application of a solid super acid, sulfated zirconia, as a catalyst for Koch carbonylation reaction
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A solid superacid, sulfated zirconia, worked well in the Koch reaction. Under optimized conditions, tertiary alcohols were selectively transformed to the corresponding carboxylic acids (34-72%), while primary alcohols were transformed to the corresponding ethers (58-72%).
- Mori, Hajime,Wada, Aya,Xu, Qiang,Souma, Yoshie
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p. 136 - 137
(2007/10/03)
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- Palladium(I) Carbonyl Cation-Catalyzed Carbonylation of Olefins and Alcohols in Concentrated Sulfuric Acid
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A new palladium catalyst was found to exhibit high catalytic activity for carbonylation of olefins and alcohols. cyclo-Bis(μ-carbonyl)dipalladium(I) cation (1) with bridging CO ligands is formed by reductive carbonylation of palladium sulfate, PdSO4, in concentrated H2SO4. When an olefin or alcohol is added, complex 1 changes to a new complex (2) with terminal CO ligands, and tertiary carboxylic acids are obtained in high yields at room temperature and atmospheric pressure of CO. IR and 13C NMR studies suggest that complex 2 may be tentatively formulated to be [Pd2(CO)2]2+, in which the terminal CO ligands are chemically equivalent. Complex 1 is a catalyst precursor, and complex 2 functions as an active species for the carbonylation of olefins and alcohols. The catalytic behavior of the palladium carbonyl catalyst supports the recently proposed reaction mechanism involving an olefin-metal-CO complex as an intermediate for the catalytic carbonylation of olefins and alcohols in strongly acidic solution.
- Xu, Qiang,Souma, Yoshie,Umezawa, Junya,Tanaka, Mutsuo,Nakatani, Hisako
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p. 6306 - 6311
(2007/10/03)
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- A New Gold Catalyst: Formation of Gold(I) Carbonyl, [Au(CO)n]+ (n = 1, 2), in Sulfuric Acid and Its Application to Carbonylation of Olefins
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A new gold catalyst, [Au(CO)n]+ (n = 1, 2), was synthesized by using a facile method from commercial gold(III) oxide, Au2O3, in concentrated H2SO4, which exhibits high catalytic activity for carbonylation of olefins. The gold monocarbonyl [Au(CO)]+ (1) and dicarbonyl [Au(CO)2]+ (2) cations coexist in H2SO4 solution, the former of which is much more stable than the latter. Both of the carbonyls show IR spectra of vCO (2194, 2208 cm-1) higher than that of free CO (2143 cm-1), indicating nonclassical (σ-only) gold-CO bonding. The gold carbonyl complexes coexisting in the concd H2SO4 solution exhibit a single resonance in the 13C NMR spectrum at 171 ppm at ambient temperature and pressure, reflecting rapid CO exchange between 1 (164 ppm) and 2 (175 ppm). The nonclassical gold(I) carbonyl solution worked as an excellent catalyst, with which olefins reacted with CO to give tert-carboxylic acids in good yields at room temperature and atmospheric pressure. The gold(I) dicarbonyl cation 2 was found to function as an active species for the carbonylation. An olefin-gold(I)-carbonyl complex was proposed as a possible intermediate in the metal carbonyl-catalyzed carbonylation in the strongly acidic medium.
- Xu, Qiang,Imamura, Yuki,Fujiwara, Masahiro,Souma, Yoshie
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p. 1594 - 1598
(2007/10/03)
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- Pyridylthio-acylanilide herbicides
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Novel herbicidally active pyridylthio-acylanilides of the formula STR1 in which R1, R2 and R3, independently of one another, represent hydrogen, halogen, cyano or trifluoromethyl or alkyl, alkoxy and alkylthio having 1 to 4 carbon atoms in each case, R4 represents halogen, methyl or methoxy, n represents a number 0, 1 or 2, z represents the group (Ia) STR2 or the group (Ib) STR3 where X represents oxygen, sulphur, an N--R10 or N--O--R11 group, or X and Rg tpgether represent the STR4 radical, and the other radicals can have various meanings. Intermediates of the formulae STR5 are also new.
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- HIGHLY SELECTIVE SYNTHESIS OF ACYCLIC TERT-ALIPHATIC CARBOXYLIC ACIDS FROM ACYCLIC TERT-ALCOHOLS USING SULFURIC ACID SUPERSATURATED WITH CARBON MONOXIDE
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The selective carboxylation of acyclic tert-aliphatic alcohols was successfully performed to produce the corresponding acyclic tert-aliphatic carboxylic acids in significantly high yields using concentrated sufuric acid supersaturated with carbon monoxide.
- Takahashi, Yukio,Yoneda, Norihiko
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p. 1945 - 1954
(2007/10/02)
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- Anti-arteriosclerotic agents
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Novel substituted arylene compounds and methods for their preparation and use are disclosed. These new compounds are useful as anti-arteriosclerotic agents.
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- SYNTHESIS OF ESTERS FROM 1-HEXANOL AND ETHYL FORMATE UNDER CONDITIONS OF SULFURIC ACID CATALYSIS
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The ethoxycarbonylation of 1-hexanol in one stage with concentrated sulfuric acid as catalyst and ethyl formate as acylating and esterifying agent was investigated.The products are mainly ethyl 2,2-dimethylpentanoate, 2-methyl-2-ethylbutyrate, and 2-ethylpentanoate and the corresponding acids.The content of the esters and acids with a quaternary carbon atom at position 2 in the reaction mixture increased with increase in the molar ratio of sulfuric acid to alcohol, with decrease in the molar ratio of ethyl formate to sulfuric acid, with increase in the rate of addition of the alcohol to the sulfuric acid, and with increase in the reaction temperature.
- Ordyan, M. B.,Stepanyan, A. A.,Pirozhkov, S. D.,Manukyan, Sh. M.,Grigoryan, V. S.,Lapidus, A. L.
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p. 1429 - 1432
(2007/10/02)
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- Preparation of 15-deoxy-16-hydroxyprostaglandins
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Analogues of PGE1 having the structural formula, STR1 in which J is R-hydroxymethylene or S-hydroxymethylene; R1 is hydrogen; R2 is hydrogen or together with R4 is a methylene chain of 2 to 3 carbon atoms such that a cycloalkyl of 5 to 6 carbon atoms inclusive is formed; R3 is hydrogen or methyl, or together with R4 is a methylene or a lower alkylated methylene chain of 2 to 5 carbon atoms such that a cycloalkyl or a lower alkylated cycloalkyl of 4 to 7 carbon atoms inclusive is formed, or together with R4 is bicycloalkyl or bicycloalkenyl moiety having the formula: STR2 SUCH THAT A BICYCLOALKYL OR BICYCLOALKENYL COMPOUND IS FORMED, WHEREIN M AND N ARE INTEGERS HAVING A VALUE FROM 0 TO 3, P IS AN INTEGER HAVING A VALUE FROM 0 TO 4 AND Q IS AN INTEGER HAVING A VALUE OF FROM 1 TO 4 AND WHEREIN THE DOUBLE BOND OF SUCH BICYCLOALKENYL IS IN THE M, N, P, OR Q BRIDGE; R4 is hydrogen or methyl or together with R2 or R3 forms a cycloalkyl or bicycloalkyl or bicycloalkenyl as defined above, or together with R5 is a methylene chain of 3 to 5 carbon atoms such that a cycloalkyl of 4 to 6 carbon atoms inclusive is formed; R5 is selected from the group consisting of hydrogen, straight-chain alkyl having from 1 to 3 carbon atoms or together with R4 forms a cycloalkyl as defined above; and R6 is hydrogen or straight-chain alkyl having from 1 to 3 carbon atoms are disclosed. Pge1 ester analogues of the above formula, limited to the structures wherein two of R2, R3 R4 and R5 form a cycloalkyl, lower alkylated cycloalkyl, bicycloalkyl or bicycloalkenyl are also disclosed. The prostaglandin analogues selectively produce bronchodilation and decrease gastric secretion in vivo. Methods of preparing the analogues and starting materials required in the synthesis of the analogues are also disclosed.
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