Harnessing hypervalent iodonium ylides as carbene precursors: C–H activation of <i>N</i>-methoxybenzamides with a Rh(<scp>iii</scp>)-catalyst
作者:Sivakalai Mayakrishnan、Masilamani Tamizmani、Naryanan Uma Maheswari
DOI:10.1039/d0cc06038k
日期:——
Hypervalentiodoniumylides expeditiously generate carbenes which undergo domino intermolecular C–H activation followed by intramolecular condensation in the presence of N-methoxybenzamide as a starting material and a Rh(III)-catalyst to afford dihydrophenanthridines. KIE studies and DFT calculations were performed to substantiate the mechanistic pathway. To extend the synthetic utilisation, fluorescent
Synthesis of dihydroindazolo[2,3-<i>f</i>]phenanthridin-5(6<i>H</i>)-ones <i>via</i> Rh(<scp>iii</scp>)-catalyzed C–H activation of 2-aryl indazoles and annulation with iodonium ylides
An efficient syntheticroute to indazole-fused dihydrophenanthridinones in excellent to almost quantitative yields under mild reaction conditions was developed. The reaction utilizes the acid-controlled Rh(III)-catalyzed C–H activation of 3-arylindazoles followed by their annulation with readily available hypervalent iodonium ylides. This methodology afforded a wide range of products that could be
开发了一种在温和反应条件下以优异至几乎定量的产率合成吲唑稠合二氢菲啶酮的有效合成路线。该反应利用酸控制的 Rh( III ) 催化的 3-芳基吲唑的 C-H 活化,然后用现成的高价碘鎓叶立德进行环化。这种方法提供了广泛的产品,只需简单的过滤即可分离,无需柱层析。此外,催化体系可以循环使用至少八次,收率很高,这可能使其适合工业生产。此外,合成的二氢吲唑并[2,3 - f ]phenanthridin-5(6 H)-表示它们可能具有作为新型荧光材料的潜在应用。
Ru(II)-Catalyzed C–H Functionalization of 2-Arylbenzimidazoles with Iodonium Ylides: A Straightforward Access to Bridgehead Polycyclic N-Heterocycles
rylimidazoles with iodonium ylides leading to substituted tetracyclic and pentacyclic bridgehead N-heterocycles, wherein iodonium ylide acts as a carbene precursor. For the first time, iodonium ylide proceeds through a Ru–carbenoid intermediate. Further, the synthetic utility of this protocol was successfully shown for gram-scale synthesis and useful synthetic transformations.
Copper(I) Iodide Catalyzed [3 + 3] Annulation of Iodonium Ylides with Pyridinium 1,4-Zwitterionic Thiolates for the Synthesis of 1,4-Oxathiin Scaffolds
作者:Àlex Díaz-Jiménez、Stuart C. D. Kennington、Anna Roglans、Anna Pla-Quintana
DOI:10.1021/acs.orglett.3c01538
日期:2023.7.7
assemble the 1,4-oxathiin core through a [3 + 3] annulation. The optimal annulation partner has been found to be the iodonium ylide of the cyclic 1,3-diketones. The developed protocol allows the synthesis of a variety of bicyclic 1,4-oxathiin derivatives under very mild conditions under copper(I) iodide catalysis. Access to benzoannulated 1,4-oxathiins has been achieved through iodine-mediated aromatization