Esterification of Tertiary Amides by Alcohols Through C−N Bond Cleavage over CeO
<sub>2</sub>
作者:Takashi Toyao、Md. Nurnobi Rashed、Yoshitsugu Morita、Takashi Kamachi、S. M. A. Hakim Siddiki、Md. A. Ali、A. S. Touchy、Kenichi Kon、Zen Maeno、Kazunari Yoshizawa、Ken‐ichi Shimizu
DOI:10.1002/cctc.201801098
日期:2019.1.9
process proceeds through rate limiting addition of a CeO2 lattice oxygen to the carbonyl group of the adsorbed acetamide species with energy barrier of 17.0 kcal/mol. This value matches well with experimental value (17.9 kcal/mol) obtained from analysis of the Arrhenius plot. Further studies by in situ FT‐IR and temperatureprogrammeddesorption using probe molecules demonstrate that both acidic and
The oxidative esterification of various aldehydes with alcohols could be achieved by a heterogeneous iron(III) catalyst supported on a ring-like POM inorganic ligand under mild conditions, affording the corresponding esters, including several drug molecules and natural products, in high yields. ESI-MS and control experiments demonstrated that POM-FeV(O) was the active catalytic species and the plausible
Bi(III) halides as efficient catalysts for the O-acylative cleavage of tetrahydrofurans: an expeditious entry to tetralins
作者:Simon J. Coles、James F. Costello、William N. Draffin、Michael B. Hursthouse、Simon P. Paver
DOI:10.1016/j.tet.2005.02.080
日期:2005.5
O-acylative cleavage of tetrahydrofurans using organic acid halides with catalytic Bi(III) halides is reported. X-ray crystallography is used to rationalise the failure of the reaction in the case of certain crowded acid chlorides, and a useful aspect of chemoselectivity is revealed. The synthetic potential of this reaction is illustrated with a highly efficient O-acylative cleavage/intramolecular
Free-Radical-Promoted Site-Selective C–H Silylation of Arenes by Using Hydrosilanes
作者:Zhengbao Xu、Li Chai、Zhong-Quan Liu
DOI:10.1021/acs.orglett.7b02717
日期:2017.10.20
silylation using hydrosilane was developed. This cross-dehydrogenative silylation enables both electron-rich and electron-poor aromatics to afford the desired arylsilanes in unique selectivity. A “para-selectivity” was observed by examination of over 54 examples. This exceptional orientation is quite different from that in Friedel–Crafts C–H silylation or transition-metal-catalyzed dehydrogenative silylation
Ir<sup>III</sup>-Catalyzed direct syntheses of amides and esters using nitriles as acid equivalents: a photochemical pathway
作者:Ranadeep Talukdar
DOI:10.1039/d0nj00002g
日期:——
unprecedented IrIII[df(CF3)ppy]2(dtbbpy)PF6-catalyzed simple photochemical process for direct addition of amines and alcohols to the relatively less reactive nitrile triple bond is described herein. Various amides and esters are synthesized as the reaction products, with nitriles being the acid equivalents. A mini-library of different types of amides and esters is made using this mild and efficient process, which
本文描述了空前的Ir III [df(CF 3)ppy] 2(dtbbpy)PF 6催化的简单光化学过程,用于将胺和醇直接加成到反应性较小的腈三键上。合成了各种酰胺和酯作为反应产物,其中腈是酸的当量。使用这种温和有效的方法可以制得不同类型的酰胺和酯的小型文库,该方法在可见光照射下(λ = 445 nm)仅使用1 mol%的光催化剂。该反应策略对于克级合成也是有效的。