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Esterification of long-chain acids and alcohols catalyzed by ferric chloride hexahydrate / Noboru Ieda ; Kshudiram Mantri ; Yasuyuki Miyata ; Akiyoshi Ozaki in Industrial & engineering chemistry research, Vol. 47 n°22 (Novembre 2008) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 47 n°22 (Novembre 2008) . - p. 8631–8638 Titre : Esterification of long-chain acids and alcohols catalyzed by ferric chloride hexahydrate Type de document : texte imprimé Auteurs : Noboru Ieda, Auteur ; Kshudiram Mantri, Auteur ; Yasuyuki Miyata, Auteur ; Akiyoshi Ozaki, Auteur Année de publication : 2008 Article en page(s) : p. 8631–8638 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Acids  Alcohols  Catalyzed  Hexahydrate Résumé : A variety of multivalent metal salt, many of them are hydrates, were screened as catalysts for the esterification of fatty acids and alcohols. These salts included chlorides, nitrates, sulfates, and acetates of Fe3+, Al3+, Ga3+, In3+, ZrO2+, HfO2+, Zn2+, Co2+, Ni2+, Mn3+, Cr3+, and Cu2+. Ferric salts, particularly, FeCl3·6H2O, were the most active among the salts screened. The esters of primary C10−C18 fatty acids and alcohols were obtained quantitatively from equimolar mixtures in the presence of FeCl3·6H2O (substrate/catalyst (S/C; mol/mol) = 200, reaction period = 6 h, in refluxing mesitylene). Esters of isostearic acid and C10–C18 fatty alcohols were obtained with large quantities and prolonged reaction periods. The esters of aromatic carboxylic acids with cetyl alcohol and bulky steroid alcohols, including cholesterol, with C8−C18 fatty acids, were obtained in high yield. The cationic cluster formed by hydrolysis of the ferric cation is proposed to be the catalytically active species. Such a catalysis is proposed to occur through the activation of the carboxylic acid by ligand exchange from water to the carboxylate moiety, followed by addition of the alcohol. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie800957b [article] Esterification of long-chain acids and alcohols catalyzed by ferric chloride hexahydrate [texte imprimé] / Noboru Ieda, Auteur ; Kshudiram Mantri, Auteur ; Yasuyuki Miyata, Auteur ; Akiyoshi Ozaki, Auteur . - 2008 . - p. 8631–8638. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 47 n°22 (Novembre 2008) . - p. 8631–8638 Mots-clés : Acids  Alcohols  Catalyzed  Hexahydrate Résumé : A variety of multivalent metal salt, many of them are hydrates, were screened as catalysts for the esterification of fatty acids and alcohols. These salts included chlorides, nitrates, sulfates, and acetates of Fe3+, Al3+, Ga3+, In3+, ZrO2+, HfO2+, Zn2+, Co2+, Ni2+, Mn3+, Cr3+, and Cu2+. Ferric salts, particularly, FeCl3·6H2O, were the most active among the salts screened. The esters of primary C10−C18 fatty acids and alcohols were obtained quantitatively from equimolar mixtures in the presence of FeCl3·6H2O (substrate/catalyst (S/C; mol/mol) = 200, reaction period = 6 h, in refluxing mesitylene). Esters of isostearic acid and C10–C18 fatty alcohols were obtained with large quantities and prolonged reaction periods. The esters of aromatic carboxylic acids with cetyl alcohol and bulky steroid alcohols, including cholesterol, with C8−C18 fatty acids, were obtained in high yield. The cationic cluster formed by hydrolysis of the ferric cation is proposed to be the catalytically active species. Such a catalysis is proposed to occur through the activation of the carboxylic acid by ligand exchange from water to the carboxylate moiety, followed by addition of the alcohol. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie800957b

Strong organic acids as efficient catalysts for the chloromethylation of m-xylene / Tohru Kishida in Industrial & engineering chemistry research, Vol. 48 N°4 (Février 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N°4 (Février 2009) . - pp. 1831–1839 Titre : Strong organic acids as efficient catalysts for the chloromethylation of m-xylene : the synthesis of 1,3-bis(chloromethyl)-4,6-dimethylbenzene Type de document : texte imprimé Auteurs : Tohru Kishida, Auteur ; Noboru Ieda, Auteur ; Takayoshi Yamauchi, Auteur Année de publication : 2009 Article en page(s) : pp. 1831–1839 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Strong  organic  acids  M-xylene  chloromethylation  Aqueous  biphasic  conditions Résumé : Strong organic acids, CCl3COOH, CHCl2COOH, CF3COOH, CH3SO3H, CF3SO3H, and p-CH3C6H4SO3H, effectively catalyzed the chloromethylation of m-xylene with hydrochloric acid and trioxane under organic and aqueous biphasic conditions. They were active enough at 2−10 wt % against m-xylene to yield chloromethyl-2,4-dimethylbenzene (I) and 1,3-bis(chloromethyl)-4,6-dimethylbenzene (II), although they accompanied trischloromethylation products, trischloromethyl-1,3-dimethylbenzenes (III). The highest yield of II, as high as around 70%, was obtained by using CF3SO3H under appropriate conditions because it has the strongest acid strength among the acids. These acids stay in aqueous phase after the catalysis, and organic products are easily separated from the reaction mixture. The reaction may start the formation of chloromethanol from formaldehyde, and strong organic acids can assist the stabilization of chloromethyl carbocation−acid complex formed by the dehydration of chloromethanol. The resulting complex gives I by nucleophilic attack at o- and p-positions of methyl groups, and II is formed through consecutive attack of the complex against I. The chloromethylation of biphenyl (BP) in the presence of strong acids also gave the chloromethylated products; however, large amounts of acid are necessary for the efficient formation of the products due to the low reactivity of BP. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8014022 [article] Strong organic acids as efficient catalysts for the chloromethylation of m-xylene : the synthesis of 1,3-bis(chloromethyl)-4,6-dimethylbenzene [texte imprimé] / Tohru Kishida, Auteur ; Noboru Ieda, Auteur ; Takayoshi Yamauchi, Auteur . - 2009 . - pp. 1831–1839. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N°4 (Février 2009) . - pp. 1831–1839 Mots-clés : Strong  organic  acids  M-xylene  chloromethylation  Aqueous  biphasic  conditions Résumé : Strong organic acids, CCl3COOH, CHCl2COOH, CF3COOH, CH3SO3H, CF3SO3H, and p-CH3C6H4SO3H, effectively catalyzed the chloromethylation of m-xylene with hydrochloric acid and trioxane under organic and aqueous biphasic conditions. They were active enough at 2−10 wt % against m-xylene to yield chloromethyl-2,4-dimethylbenzene (I) and 1,3-bis(chloromethyl)-4,6-dimethylbenzene (II), although they accompanied trischloromethylation products, trischloromethyl-1,3-dimethylbenzenes (III). The highest yield of II, as high as around 70%, was obtained by using CF3SO3H under appropriate conditions because it has the strongest acid strength among the acids. These acids stay in aqueous phase after the catalysis, and organic products are easily separated from the reaction mixture. The reaction may start the formation of chloromethanol from formaldehyde, and strong organic acids can assist the stabilization of chloromethyl carbocation−acid complex formed by the dehydration of chloromethanol. The resulting complex gives I by nucleophilic attack at o- and p-positions of methyl groups, and II is formed through consecutive attack of the complex against I. The chloromethylation of biphenyl (BP) in the presence of strong acids also gave the chloromethylated products; however, large amounts of acid are necessary for the efficient formation of the products due to the low reactivity of BP. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8014022