99515-50-1Relevant academic research and scientific papers
Ligand-Controlled C?O Bond Coupling of Carboxylic Acids and Aryl Iodides: Experimental and Computational Insights
Li, Li,Song, Feifei,Zhong, Xiumei,Wu, Yun-Dong,Zhang, Xinhao,Chen, Jiean,Huang, Yong
supporting information, p. 126 - 132 (2019/11/28)
Palladium-catalyzed cross-coupling reactions between carboxylic acids and aryl halides have several possible competitive pathways. Decarboxylative C?C bond coupling and C?H arylation are well established in the literature. However, direct C?O bond coupling between carboxylic acids and aryl halides has received little success. In this report, we describe a protocol for exclusive C?O bond formation, enabled by a bidentate N,N-ligand such as 1,10-phenanthroline. The reaction is general for a broad range of carboxylic acids and iodoarenes. Experimental evidence and computational results suggest a high energy barrier for the alternative pathway of decarboxylative carbon-carbon bond coupling. (Figure presented.).
MnO2?Fe3O4 Magnetic Nanoparticles as Efficient and Recyclable Heterogeneous Catalyst for Benzylic sp3 C?H Oxidation
Pandey, Akanksha M.,Agalave, Sandip G.,Vinod, Chathakudath P.,Gnanaprakasam, Boopathy
supporting information, p. 3414 - 3423 (2019/10/19)
Herein, we report a highly chemoselective and efficient heterogeneous MnO2?Fe3O4 MNP catalyst for the oxidation of benzylic sp3 C?H group of ethers using TBHP as a green oxidant to afford ester derivatives in high yield under batch/continuous flow module. This catalyst was also effective for the benzylic sp3 C?H group of methylene derivatives to furnish the ketone in high yield which can be easily integrated into continuous flow condition for scale up. The catalyst is fully characterized by spectroscopic techniques and it was found that 0.424 % MnO2?Fe3O4 catalyzes the reaction; the magnetic nanoparticles of this catalyst could be easily recovered from the reaction mixture. The recovered catalyst was recycled for twelve cycles without any loss of the catalytic activity. The advantages of MnO2?Fe3O4 MNP are its catalytic activity, easy preparation, recovery, and recyclability, gram scale synthesis with a TOF of up to 14.93 h?1 and low metal leaching during the reaction.
Palladium-catalyzed non-directed C[sbnd]H benzoxylation of simple arenes with iodobenzene dibenzoates
Li, Li,Wang, Ying,Yang, Tingting,Zhang, Qian,Li, Dong
supporting information, p. 5859 - 5863 (2016/12/09)
A palladium-catalyzed non-directed C[sbnd]H benzoxylation of simple arenes with iodobenzene dibenzoates as both benzoxylate source and oxidant has been developed. The catalytic system was greatly promoted by a pyridine ligand. Good functional groups tolerance was showed in both hypervalent iodine reagents and arene substrates, which can be used for synthesis of aryl benzoates through simple aromatic compounds.
Montmorillonite K10 and KSF clays as acidic and green catalysts for effective esterification of phenols and alcohols under MWI
Marvi,Fekri,Takhti
, p. 1837 - 1840 (2015/01/09)
Montmorillonite K-10 and KSF clays catalyze esterification of phenols and alcohols under microwave irradiation and solvent-free conditions in high yields within seconds.
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.
Ruthenium/NHC-catalyzed tandem benzylic oxidation/oxidative esterification of benzylic alcohols with phenols
Zhang, Di,Pan, Changduo
experimental part, p. 41 - 45 (2012/06/18)
An efficient methodology to access benzoate derivatives via tandem benzylic oxidation/oxidative esterification of benzylic alcohols with phenols catalyzed by ruthenium/NHC was developed. This operationally simple one-pot process uses O2 as the clean oxidant, producing esters in good to excellent yields.
Palladium/NHC-catalyzed tandem benzylic oxidation/oxidative esterification of benzylic alcohols with phenols
Luo, Fang,Pan, Changduo,Cheng, Jiang,Chen, Fan
supporting information; experimental part, p. 5878 - 5882 (2011/09/12)
A palladium/NHC-catalyzed tandem benzylic oxidation/oxidative esterification of benzylic alcohols with phenols to access aryl benzoate derivatives is described. The procedure tolerates a series of functional groups, such as methoxy, nitro, cyano, chloro, fluoro and bromo groups. Thus, it represents a practically alternative method to access aryl benzoate derivatives.
17O NMR study of ortho and alkyl substituent effects in substituted phenyl and alkyl esters of benzoic acids
Nummert, Vilve,Maeemets, Vahur,Piirsalu, Mare,Vahur, Signe,Koppel, Ilmar A.
experimental part, p. 1737 - 1763 (2012/04/17)
17O NMR spectra for 44 ortho-, meta- and para-substituted phenyl and alkyl benzoates (C6H5CO2C 6H4-X, C6H5CO2R) at natural abundance in acetonitrile were re
Palladium/NHC-catalyzed oxidative esterification of aldehydes with phenols
Zhang, Manli,Zhang, Shouhui,Zhang, Guoying,Chen, Fan,Cheng, Jiang
experimental part, p. 2480 - 2483 (2011/05/16)
A palladium-catalyzed oxidative esterification of aldehydes with phenols is described, using air as the clean oxidant. This reaction tolerates many functional groups, providing esters with yields ranging from moderate to excellent.
Easily prepared azopyridines as potent and recyclable reagents for facile esterification reactions. An efficient modified mitsunobu reaction
Iranpoor, Nasser,Firouzabadi, Habib,Khalili, Dariush,Motevalli, Somayeh
, p. 4882 - 4887 (2008/09/21)
(Chemical Equation Presented) The 2,2′-, 3,3′-, and 4,4′-azopyridines (azpy) and their alkyl pyridinium ionic liquids were studied as a new class of electron-deficient reagents for Mitsunobu esterification reactions. Among these compounds, 4,4′-azopyridine was found to be the most suitable one for esterification and thioesterification reactions. This new reagent promises to provide general and complementary solutions for separation problems in Mitsunobu reactions without restricting the reaction scope and facilitates the isolation of its hydrazine byproduct. The pyridine hydrazine byproduct can be simply recycled to its azopyridine by an oxidation reaction.
