Direct esterification of carboxylicacids with arylboronic acids has been successfully developed employing methyl propiolate as an activating reagent. This transformation was performed through a process of enol ester intermediate‐induced metal‐free oxidative coupling. Metal‐free, simple operation, good functional group tolerance, all of these indicate that this method is an adoptable approach for the
Transition-Metal-Free Poly(thiazolium) Iodide/1,8-Diazabicyclo[5.4.0]undec-7-ene/Phenazine-Catalyzed Esterification of Aldehydes with Alcohols
作者:Supill Chun、Young Keun Chung
DOI:10.1021/acs.orglett.7b01617
日期:2017.7.21
Poly(3,4-dimethyl-5-vinylthiazolium) iodide was used as a polymer precatalyst in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) and phenazine for the oxidative esterification of aldehydes with alcohols. Selective functionalization of OH groups was achieved in the presence of NH2 groups. The poly(thiazolium) iodide/DBU/phenazine system exhibited excellent catalytic activity and could be reused
Hydrogen-bond-assisted transition-metal-free catalytic transformation of amides to esters
作者:Changyu Huang、Jinpeng Li、Jiaquan Wang、Qingshu Zheng、Zhenhua Li、Tao Tu
DOI:10.1007/s11426-020-9883-3
日期:2021.1
interest in synthetic chemistry, biological process and pharmaceutical industry. Transition-metal, luxury ligand or excess base were always vital to the transformation. Here, we developed a transition-metal-free hydrogen-bond-assisted esterification of amides with only catalytic amount of base. The proposed crucial role of hydrogen bonding for assisting esterification was supported by control experiments
palladacycle‐catalyzed aromatic carbonylation reaction of arylformates with aryl iodides or bromides has been developed. Commercially available and easily prepared arylformates were employed as carbonyl sources without the use of externalcarbonmonoxide. The present catalytic system shows broad functional group tolerance and affords aryl benzoate derivatives in good to excellent yields.
Mechanically induced solvent-free esterification method at room temperature
作者:Lei Zheng、Chen Sun、Wenhao Xu、Alexandr V. Dushkin、Nikolay Polyakov、Weike Su、Jingbo Yu
DOI:10.1039/d0ra09437d
日期:——
Herein, we describe two novel strategies for the synthesis of esters, as achieved under high-speed ball-milling (HSBM) conditions at room temperature. In the presence of I2 and KH2PO2, the reactions afford the desired esterification derivatives in 45% to 91% yields within 20 min of grinding. Meanwhile, using KI and P(OEt)3, esterification products can be obtained in 24% to 85% yields after 60 min of