1523-13-3Relevant academic research and scientific papers
Reactions of aryl benzoates with potassium aryloxides: Solvent effects on reaction pathway and kinetics
Khalfina, Irina A.
, p. 302 - 314 (2015)
Temperature dependences of the relative reactivity of potassium aryloxides XC6H4O-K+ toward 2,4-dinitrophenyl benzoate in 50 mol% dimethylformamide (DMF)-50 mol% H2O mixture have been studied using the competitive reactions technique. Correlation analyses of the relative rate constants kX/kH and differences in the activation parameters (ΔΔCyrillic capital letter en≠ and ΔΔS≠) of the competitive reactions have revealed the existence of two isokinetic series of the reactions of 2,4-dinitrophenyl benzoate with potassium aryloxides with electron-donating substituent (EDS) and electron-withdrawing substituent (EWS), respectively. We have investigated the effect of the substituent X on the activation parameters for each isokinetic series and concluded that the mechanism of the reactions of 2,4-dinitrophenyl benzoate with potassium aryloxides XC6H4O-K+ in 50 mol% DMF-50 mol% H2O mixture is the same as in DMF. Analysis of the obtained data with using the method of two-dimensional reaction coordinate diagram leads to the conclusion that the variation of the solvent from DMF to 50 mol% DMF-50 mol% H2O mixture affects the reaction pathway. The rate constant kX for the reaction of 3-nitrophenyl benzoate with potassium 4-methoxyphenoxide and the relative rate constants kX/kH for the reaction of 3-nitrophenyl benzoate with potassium aryloxides XC6H4O-K+ with EDS were measured in 50 mol% DMF-50 mol% H2O mixtures at 25C, and it has been shown that the addition of water to DMF does not change the mechanism but slows down these reactions.
Copper-mediated simple and direct aerobic oxidative esterification of arylacetonitriles with alcohols/phenols
Dong, Jianyu,Chen, Xiuling,Ji, Fangyan,Liu, Lixin,Su, Lebin,Mo, Min,Tang, Jian-Sheng,Zhou, Yongbo
, (2020/10/20)
A simple and direct aerobic oxidative esterification reaction of arylacetonitriles with alcohols/phenols is achieved in the presence of a copper salt and molecular oxygen, which produces a broad range of aryl carboxylic acid esters in good to high yields. Copper salt plays multiple roles in the transformation, which allows the oxygenation of C-H bond, cleavage of inert C-C bond, and formation of C-O bond in one pot without the assistance of any of the acids, bases, ligands, and so on. The reaction provides a simple, direct, and efficient protocol towards functionalized esters, especially aryl benzoates, from readily available starting materials.
Electrodimerization of N-Alkoxyamides for Zinc(II) Catalyzed Phenolic Ester Synthesis under Mild Reaction Conditions
Subramanian, Kripa,Yedage, Subhash L.,Bhanage, Bhalchandra M.
, p. 2511 - 2521 (2018/05/14)
An electrochemical On-Off method for phenolic ester synthesis from N-alkoxyamides has been reported. This one-pot protocol begins with rapid and selective electrodimerization of the amide using n-Bu4NI (TBAI) as an electrocatalyst. The reaction proceeds further in the absence of current via Zn catalyzed C?N bond activation of the amide dimer followed by its coupling with phenol to form the ester. The present methodology is ligand-free and takes place under mild reaction conditions. This transformation incorporates a wide variety of phenols and amide substrates leading to the formation of functionalized esters highlighting its versatility. (Figure presented.).
Pd/C catalyzed phenoxycarbonylation using: N -formylsaccharin as a CO surrogate in propylene carbonate, a sustainable solvent
Gautam, Prashant,Kathe, Prasad,Bhanage, Bhalchandra M.
supporting information, p. 823 - 830 (2017/08/15)
This work reports the first Pd/C catalyzed phenoxycarbonylation of aryl iodides using N-formylsaccharin as a CO surrogate. Advantageously, the reaction could be carried out in propylene carbonate, an environmentally benign and sustainable polar aprotic solvent under CO surrogacy. Using N-formylsaccharin as a CO surrogate allows the usage of cheaper and readily available phenols as the coupling partner. A range of phenyl esters could be synthesized under mild, co-catalyst free, ligand free and additive free conditions, including multi-substituted novel phenyl esters. The Pd/C catalyst could be recycled up to four times with only a slight loss in activity. The reaction could be scaled up to gram scale synthesis.
Ph3P-I2 mediated aryl esterification with a mechanistic insight
Phakhodee, Wong,Duangkamol, Chuthamat,Pattarawarapan, Mookda
supporting information, p. 2087 - 2089 (2016/04/26)
In order to better understand the reaction mechanism and to obtain optimal conditions, the Ph3P-I2/Et3N mediated aryl esterification reaction was thoroughly investigated. Using a specific reagent addition sequence, the reaction proceeds remarkably well especially with acidic substrates. 31P NMR studies revealed that the formation of an aryloxyphosphonium salt is crucial in governing the reaction path toward the formation of phenolic esters.
Solid-Phase Benzoylation of Phenols and Alcohols in Microwave Reactor: An Ecofriendly Protocol
Chakraborty, Suchandra,Saha, Ahana,Basu, Kaushik,Saha, Chandan
supporting information, p. 2331 - 2343 (2015/10/12)
An efficient solid-phase benzoylation of phenols and alcohols was developed under microwave irradiation. A stoichiometric amount of benzoyl chloride was sufficient to carry out the reaction. This benzoylation features short reaction time, good yields, and easy workup procedures. Furthermore, the scope of the reaction was extended to prepare 3,5-dinitrobenzoyl derivatives of alcohols.
Metal-free synthesis of aryl esters by coupling aryl carboxylic acids and aryl boronic acids
Ruso, Jayaraman Sembian,Rajendiran, Nagappan,Kumaran, Rajendran Senthil
supporting information, p. 2345 - 2347 (2014/05/06)
A facile synthesis of aryl esters is developed by coupling aryl carboxylic acids and aryl boronic acids in the presence of PhI(OAc)2 and carbonyl diimidazole. A wide range of functional groups were tolerant to the metal-free reaction condition that led to the desired products in good yields.
Enthalpy-entropy correlations in reactions of aryl benzoates with potassium aryloxides in dimethylformamide
Khalfina, Irina A.,Vlasov, Vladislav M.
, p. 266 - 282 (2013/05/21)
Temperature dependences of the relative reactivity of potassium aryloxides XC6H4O-K+ toward 4-nitrophenyl (1), 3-nitrophenyl (2), 4-chlorophenyl (3), and phenyl (4) benzoates in dimethylformamide (DMF) were studied using the competitive reactions technique. The rate constants kX for the reactions of 1 with potassium 4-cyanophenoxide, 2 with potassium 3-bromophenoxide, 3 with potassium 3-bromo-, 4-bromo-, and unsubstituted phenoxides, 4 with potassium 4-methoxy- and 3-methylphenoxides were measured at 25°C. Correlation analysis of the relative rate constants kX/kH(3-Me) and differences in the activation parameters (δδH≠and δ δS ≠) of competitive reactions revealed the existence of six isokinetic series. We investigated the substituent effect of X on the activation parameters for each isokinetic series and concluded that the reactions of aryl benzoates PhCO2C6H4Y with potassium aryloxides in DMF proceed via a four-step mechanism. The large ρ0(Y) and ρXY values at 25°C obtained for the reactions of 1-3 with potassium aryloxides with an electron-donating substituent refer to the rate-determining formation of the spiro-σ-complex. The Hammett plots for the reactions of 1 and 2 exhibit a downward curvature, causing the motion of the transition state for the rate-determining step according to a Hammond effect as the substituent in aryloxide changes from electron-donating to electron-withdrawing. Analysis of data in the terms of two-dimensional reaction coordinate diagrams leads to the conclusion that significant anti-Hammond effects arise in the cases of ortho-substituted and unsubstituted substrates. It was shown that the isokinetic and compensation effects observed for the reactions of aryl benzoates with potassium aryloxides in DMF can be interpreted in the terms of the electrostatic bonding between the reaction centers.
Green and efficient method for the acylation of amines and phenols in the presence of hydrotalcite in water
Massah, Ahmad Reza,Toghyani, Mitra,Najafabadi, Batool Hojati
, p. 603 - 605,3 (2020/09/16)
In this study a mild, efficient and environmentally friendly method has been developed for the synthesis of amides and esters in the presence of hydrotalcite in water at room temperature. Different types of amines and phenols have been used and in all cases the products were obtained in moderate to high yields after an easy work-up. This method follows the principles of green chemistry.
Enthalpy-entropy correlations in reactions of 2,4-dinitrophenyl benzoate with phenols in the presence of potassium hydrogen carbonate and with potassium phenoxides in dimethylformamide
Khalfina,Vlasov
experimental part, p. 845 - 854 (2011/10/19)
Temperature dependences of the relative reactivity of substituted phenols RC6H4OH in the presence of potassium hydrogen carbonate and of potassium phenoxides RC6H4O-K + toward 2,4-dinitrophenyl benzoate in dimethylformamide were studied using the competitive reactions technique. Correlation analysis of the relative rate constants kR/kH and differences in the activation parameters (ΔΔH{double barred pipe} and ΔΔS{double barred pipe}) of competitive reactions revealed the existence of two isokinetic series for each type of nucleophiles. The mechanism of transesterification was interpreted in terms of an approach based on analysis of the effect of substituent in the nucleophile on the activation parameters. Pleiades Publishing, Ltd., 2011.
