Nickel-Catalyzed C−S Bond Formation via Decarbonylative Thioetherification of Esters, Amides and Intramolecular Recombination Fragment Coupling of Thioesters
A nickelcatalyzed cross‐coupling protocol for the straightforward C−Sbond formation has been developed. Various mercaptans and a wide range of ester and amide substrates bearing various substituents were tolerated in this process which afforded products in good to excellent yields. Furthermore, an intramolecular protocol for the synthesis of thioethers starting from thioesters has been developed
Ligand-Controlled Chemoselective C(acyl)–O Bond vs C(aryl)–C Bond Activation of Aromatic Esters in Nickel Catalyzed C(sp<sup>2</sup>)–C(sp<sup>3</sup>) Cross-Couplings
converted into the alkylated arenes and ketone products, respectively. The utility of this newly developed protocol was demonstrated by its wide substrate scope, broad functional group tolerance and application in the synthesis of keyintermediates for the synthesis of bioactive compounds. DFT studies on the oxidative addition step helped rationalizing this intriguing reaction chemoselectivity: whereas
Fluoride anion-initiated bis-trifluoromethylation of phenyl aromatic carboxylates with (trifluoromethyl)trimethylsilane
作者:Kenjiro Takahashi、Yusuke Ano、Naoto Chatani
DOI:10.1039/d0cc04826g
日期:——
carboxylates with (trifluoromethyl)trimethylsilane (Me3SiCF3) that results in the formation of O-silyl-protected 2-aryl-1,1,1,3,3,3-hexafluoroisopropanols is reported. A phenoxide anion, generated during the trifluoromethylation of the phenyl carboxylate, also activates the Me3SiCF3, which permits a catalytic amount of the fluoride anion source to be used. Various functional groups, which can be used for further
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
Switchable Selectivity in the Pd-Catalyzed Alkylative Cross-Coupling of Esters
作者:Jeanne Masson-Makdissi、Jaya Kishore Vandavasi、Stephen G. Newman
DOI:10.1021/acs.orglett.8b01646
日期:2018.7.6
The Pd-catalyzed cross-coupling of phenyl esters and alkyl boranes is disclosed. Two reaction modes are rendered accessible in a selective fashion by interchange of the catalyst. With a Pd–NHC system, alkyl ketones can be prepared in good yields via a Suzuki–Miyaurareaction proceeding by activation of the C(acyl)–O bond. Use of a Pd–dcype catalyst enables alkylated arenes to be synthesized by a modified