Quaternary Phosphonium Carboxylates: Structure, Dynamics and Intriguing Olefination Mechanism
作者:Kirill Nikitin、Anna C. Vetter、Helge Müller-Bunz、Jimmy Muldoon
DOI:10.1055/s-0037-1610788
日期:2022.4
We have earlier shown how the Wittig chemistry can be done using novel Eigenbase phosphonium carboxylate reagents. Here we discuss the phenomenon of ion pairing, their solution tautomerism, solid-state structure, and mechanistic aspects of olefination. The results point to a complex process involving unfamiliar H-bond-driven ion-pair equilibria followed by standard Wittig reaction steps.
Potassium <i>tert</i>-Butoxide Promoted Intramolecular Arylation via a Radical Pathway
作者:Daniela Sustac Roman、Yoko Takahashi、André B. Charette
DOI:10.1021/ol201160s
日期:2011.6.17
Potassium tert-butoxide mediated intramolecular cyclization of aryl ethers, amines, and amides was efficiently performed under microwave irradiation to provide the corresponding products in high regioisomeric ratios. The reaction proceeds via single-electron transfer to initiate the formation of an arylradical, followed by a kinetically favored 5-exo-trig and subsequent ring expansion.
Hf(OTf)<sub>4</sub>-Catalyzed highly diastereoselective synthesis of 1,3-disubstituted tetralin derivatives via benzylic C(sp<sup>3</sup>)–H bond functionalization
作者:Taira Yoshida、Keiji Mori
DOI:10.1039/c7cc01717k
日期:——
A highly diastereoselective synthesis of 1,3-disubstituted tetralin derivatives was achieved via Hf(OTf)4-catalyzed benzylic C(sp3)-H bond functionalization.
Palladium Nanoparticles Supported on Cellulosic Paper as Multifunctional Catalyst for Coupling and Hydrogenation Reactions
作者:Abdul Nasar Kalanthoden、Md. Hasan Zahir、Md. Abdul Aziz、Basmah Al‐Najar、S. Kutti Rani、M. Nasiruzzaman Shaikh
DOI:10.1002/asia.202101195
日期:2022.2
This work describes the fabrication of a recyclable Pd-based catalyst on a support derived from cellulose tissue paper and its application as a multifunctional catalyst for C−C bond formation and transfer hydrogenation reaction in water.
Strategy for Overcoming Full Reversibility of Intermolecular Radical Addition to Aldehydes: Tandem C–H and C–O Bonds Cleaving Cyclization of (Phenoxymethyl)arenes with Carbonyls to Benzofurans
作者:Hong-Xing Zheng、Xiang-Huan Shan、Jian-Ping Qu、Yan-Biao Kang
DOI:10.1021/acs.orglett.8b01207
日期:2018.6.1
An intermolecular addition of carbon radicals enabled by a cascade radical coupling strategy is developed. It includes an intermolecular alkyl radical addition to a carbonyl group followed by an intramolecular alkoxy radical addition to haloarenes and produces substituted benzofurans in high yields. The radical nature of this reaction is explored by radical trapping experiments and EPR analysis. The