5458-59-3Relevant academic research and scientific papers
Synthesis of Layered Disodium (or Dipotassium) Tetrakis-(octanoate-o)-Zinc(II) and Preliminary Investigation of the Catalytic Activity in the Esterification of Octanoic Acid with Isopropanol
Maruyama, Swami Arêa,Zawadzki, Sonia Faria,Wypych, Fernando
, p. 726 - 733 (2017)
This paper reports the synthesis of layered zinc/sodium and zinc/potassium octanoates (A2[Zn(C8H15O2)4], A = Na+ or K+), two underexplored carboxylates, through reaction of the octanoate of the desired alkali metal with a zinc salt. After drying and chemical characterization, their catalytic activities were tested in the esterification of octanoic acid with isopropanol. Conversion values were high for the reactions conducted under following conditions: temperature 155°C, isopropanol/octanoic acid molar ratio = 8: 1, catalyst/ octanoic acid ratio 7 wt %, and reaction time 2 h. Isolation of the catalysts after esterification showed that the materials were converted into zinc octanoate in situ.
1,3-Dibromo-5,5-dimethylhydantoin as a Precatalyst for Activation of Carbonyl Functionality
?ebular, Klara,Bo?i?, Bojan ?.,Stavber, Stojan
supporting information, (2019/08/01)
Activation of carbonyl moiety is one of the most rudimentary approaches in organic synthesis and is crucial for a plethora of industrial-scale condensation reactions. In esterification and aldol condensation, which represent two of the most important reactions, the susceptibility of the carbonyl group to nucleophile attack allows the construction of a variety of useful organic compounds. In this context, there is a constant need for development of and improvement in the methods for addition-elimination reactions via activation of carbonyl functionality. In this paper, an advanced methodology for the direct esterification of carboxylic acids and alcohols, and for aldol condensation of aldehydes using widely available, inexpensive, and metal-free 1,3-dibromo-5,5-dimethylhydantoin under neat reaction conditions is reported. The method is air- and moisture-tolerant, allowing simple synthetic and isolation procedures for both reactions presented in this paper. The reaction pathway for esterification is proposed and a scale-up of certain industrially important derivatives is performed.
Oxidative esterification of aliphatic aldehydes and alcohols with ethanol over gold nanoparticle catalysts in batch and continuous flow reactors
Taketoshi,Ishida,Murayama, Toru,Honma, Tetsuo,Haruta, Masatake
, (2019/08/26)
Selective esterification of aliphatic aldehydes and alcohols with ethanol in the absence of a base is a more difficult reaction than that with methanol. Gold nanoparticles on ZnO were found to catalyze the oxidative esterification of octanal to ethyl octanoate with high selectivity. In addition, it was found that Au/ZnO was the most effective catalyst for yielding the desired ethyl ester without a base by direct esterification of 1-octanol with ethanol. As far as we know, this is the first report on oxidative esterification to give aliphatic ethyl esters from less reactive aliphatic alcohols and aldehydes without a base. The optimal size of gold NPs ranged from 2 to 6 nm and the presence of Au(0) was indispensable for this reaction. Au/ZnO exhibited the highest catalytic activity in both batch and flow reactors. The conversion was maintained for more than 20 h with 95% selectivity to the desired ethyl ester in the flow system.
Esterification of aryl/alkyl acids catalysed by n-bromosuccinimide under mild reaction conditions
?ebular, Klara,Bo?i?, Bojan ?.,Stavber, Stojan
, (2018/09/10)
N-halosuccinimides (NXSs) are well-known to be convenient, easily manipulable and low-priced halogenation reagents in organic synthesis. In the present work, N-bromosuccinimide (NBS) has been promoted as the most efficient and selective catalyst among the NXSs in the reaction of direct esterification of aryl and alkyl carboxylic acids. Comprehensive esterification of substituted benzoic acids, mono-, di- and tri-carboxy alkyl derivatives has been performed under neat reaction conditions. The method is metal-free, air- and moisture-tolerant, allowing for a simple synthetic and isolation procedure as well as the large-scale synthesis of aromatic and alkyl esters with yields up to 100%. Protocol for the recycling of the catalyst has been proposed.
Use of Lecitase-Ultra immobilized on styrene-divinylbenzene beads as catalyst of esterification reactions: Effects of ultrasounds
Alves, Joana S.,Garcia-Galan, Cristina,Danelli, Daiane,Paludo, Natália,Barbosa, Oveimar,Rodrigues, Rafael C.,Fernandez-Lafuente, Roberto
, p. 27 - 32 (2015/08/06)
Abstract In this work it was evaluated for the first time, the ester synthesis catalyzed by the phospholipase Lecitase-Ultra immobilized styrene-divinylbenzene beads (MCI-Lecitase), comparing the mechanical stirring and the ultrasonic energy. It was studied the specificity of the enzyme using carboxylic acids from C4 to C18, as well as the effects of alcohol chain, organic solvents, biocatalyst content, reaction temperature and substrate concentration. Caprylic and myristic acids were those with the highest reaction rates and yields, using ethanol as substrate. The shorter the alcohol chain, the higher the enzyme activity. Regarding the secondary alcohols, while MCI-Lecitase had no activity versus isopropanol, using 2-pentanol the activity was similar to that with 1-pentanol. Comparing the agitation systems, MCI-Lecitase presented an initial reaction rate more than 2-times higher in the ultrasound-assisted reaction than under traditional mechanical stirring. Moreover, under ultrasonic energy the maximum rate was achieved using 0.5 M of substrates, while under mechanical stirring the maximum enzyme activity was reached at 0.3 M of substrates. Concerning the operational stability, MCI-Lecitase was quite unstable, losing its activity after 6 reaction cycles. By adding molecular sieves in the reaction medium, MCI-Lecitase retained 30% of its initial activity after 6 cycles.
Transformations of peroxide olefin ozonolysis products under the action of hydroxylamine and semicarbazide hydrochlorides in isopropyl alcohol
Ishmuratov,Legostaeva,Garifullina,Botsman,Idrisova,Muslukhov,Ishmuratova,Tolstikov
, p. 1409 - 1414 (2014/01/06)
Hydroxylamine and semicarbazide hydrochlorides were shown to be efficient as reducing agents toward peroxide products of ozonolysis of various olefins with different degrees of substitution. The rate of the transformations aldehyde → aldehyde oxime → nitr
Rhenium complex-catalyzed acylative cleavage of ethers with acyl chlorides
Umeda, Rui,Nishimura, Takashi,Kaiba, Kenta,Tanaka, Toshimasa,Takahashi, Yuuki,Nishiyama, Yutaka
experimental part, p. 7217 - 7221 (2011/10/08)
It was found that rhenium complex was an efficient catalyst for the acylative cleavage of C-O bond of ethers with acyl chlorides. When acyclic ethers were allowed to react with acyl chlorides in the presence of a catalytic amount of ReBr(CO)5, acylative cleavage of C-O bond of acyclic ethers smoothly proceeded to give the corresponding esters in moderate to good yields. Similarly, cyclic ethers were acylative cleaved by acyl chlorides to give the corresponding chloro substituted esters in good yields by the use of Re 2O7 catalyst.
Rhenium complex as a useful catalyst for acylative cleavage of ethers
Umeda, Rui,Kaiba, Kenta,Tanaka, Toshimasa,Takahashi, Yuuki,Nishimura, Takashi,Nishiyama, Yutaka
experimental part, p. 3089 - 3091 (2011/02/25)
It was found that a rhenium complex such as ReBr(CO)5 acts as an efficient catalyst for the acylative cleavage of the carbon-oxygen bond of ethers with acyl chloride, giving the corresponding esters in moderate to good yields.
Scandium triflate catalyzed transesterification of carboxylic esters
Remme, Nicole,Koschek, Katharina,Schneider, Christoph
, p. 491 - 493 (2007/12/27)
The direct transesterification of carboxylic esters is efficiently catalyzed with Sc(OTf)3 (10 mol%) in boiling alcoholic solvent. Methyl, ethyl, isopropyl, and allyl esters were prepared from a broad range of different substrates in high yields. The application of microwave irradiation led to significantly reduced reaction times. Georg Thieme Verlag Stuttgart.
Solvent-free esterification catalyzed by surfactant-combined catalysts at room temperature
Gang, Li,Xinzong, Li,Eli, Wumanjiang
, p. 348 - 351 (2008/02/10)
Solvent-free esterifications of various carboxylic acids and alcohols can be catalyzed by surfactant-combined catalysts dodecylbenzene sulfonic acid (DBSA) and copper dodecylbenzene sulfonate (CDBS) in moderate to excellent yield at room temperature. The esterification method has two notable advantages: first, there is no need for any solvent, even water, and secondly, no need for energy, the reaction can proceed smoothly at room temperature. The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.
