Use of Strain-Release for the Diastereoselective Construction of Quaternary Carbon Centers
作者:Tobias Pinkert、Mowpriya Das、Malte L. Schrader、Frank Glorius
DOI:10.1021/jacs.1c03492
日期:2021.5.26
formation of quaternary carbon centers with excellent diastereoselectivity via a strain-release protocol. An organometallic species is generated by Cp*Rh(III)-catalyzed C–H activation, which is then coupled with strained bicyclobutanes (BCBs) and a prochiral carbon electrophile in a three-component reaction. This work illustrates a rare example of BCBs in transition metal catalysis and demonstrates their
Palladium-Catalyzed Oxidative Ethoxycarbonylation of Aromatic C−H Bond with Diethyl Azodicarboxylate
作者:Wing-Yiu Yu、Wing Nga Sit、Kin-Man Lai、Zhongyuan Zhou、Albert S. C. Chan
DOI:10.1021/ja710555g
日期:2008.3.1
(DEAD) together with Oxone or K2S2O8. Substrates such as 2-arylpyridines, pyrrolidinone, acetylindoline, quinoline, and oximes were ethoxycarbonylated with excellent chemo- and regioselectivities. The catalytic reaction is probably initiated by chelation-assisted cyclopalladation of the ortho-C−H bond. Preliminary studies suggested that reactive ethoxyacyl radicals generated from thermal decomposition
Palladium-catalyzed C–H activation/C–C cross-coupling reactions via electrochemistry
作者:Cong Ma、Chuan-Qi Zhao、Yi-Qian Li、Li-Pu Zhang、Xue-Tao Xu、Kun Zhang、Tian-Sheng Mei
DOI:10.1039/c7cc07429h
日期:——
Palladium-catalyzed C–H activation/C–C cross-couplingreactions have emerged as attractive tools for organic synthesis. Typically, these reactions require stoichiometric chemical oxidants and exogenous ligands to regenerate the palladium catalyst and promote reductive elimination respectively. However, there are significant disadvantages associated with the use of traditional stoichiometric oxidants
Ceric Ammonium Nitrate (CAN) Promoted Pd<sup>II</sup>-Catalyzed Substrate-Directed<i>o</i>-Benzoxylation and Decarboxylative<i>o</i>-Aroylation
作者:Sourav Kumar Santra、Arghya Banerjee、Nilufa Khatun、Bhisma K. Patel
DOI:10.1002/ejoc.201403367
日期:2015.1
Inexpensive cericammoniumnitrate (CAN) is an efficient oxidant for the Pd-catalyzed substrate-directed o-benzoxylation and decarboxylative o-aroylation processes. In the presence of CAN, the reaction of directing arenes with carboxylic acids resulted in o-benzoxylated products, whereas a decarboxylative o-aroylation occurred by using α-keto acids, which led to the formation of o-aroylation products
廉价的硝酸铈铵 (CAN) 是 Pd 催化的底物导向邻苯甲氧基化和脱羧邻芳酰化过程的有效氧化剂。在 CAN 存在下,定向芳烃与羧酸反应生成邻苯甲酰化产物,而使用 α-酮酸发生脱羧邻芳酰化,从而形成邻芳酰化产物。
Palladium-Catalyzed C(sp2)-H Bond Alkylation of Ketoximes by Using the Ring-Opening of Epoxides
A palladium-catalyzed ortho-directed alkylation of O-methyl ketoximes that proceeds through a regioselective ring-opening reaction of epoxides has been demonstrated. This C(sp2)–H activation/alkylation protocol was carried out in pivalic acid/1,1,1,3,3,3-hexafluoro-2-propanol (PivOH/HFIP, 2:8) as the solvent and was applied to various O-methyl ketoximes that contain either electron-donating or electron-withdrawing