Iridium(III)-Catalyzed Selective and Mild C-H Amidation of Cyclic <i>N</i>
-Sulfonyl Ketimines with Organic Azides
作者:Manikantha Maraswami、Gang Chen、Teck-Peng Loh
DOI:10.1002/adsc.201700785
日期:2018.2.1
A general protocol for iridium catalyzed direct C−H amidation of cyclic N-sulfonyl ketimines using sulfonyl, acyl and arylazides as nitrogen source is reported herein. The reaction takes place at roomtemperature with acyl and arylazides, while an elevated temperature needed with sulfonylazides to furnish aminated sultams in excellent yields with complete chemo and regioselectivity, thus providing
Rhodium‐Catalyzed Spirocyclic Sultam Synthesis by [3+2] Annulation with Cyclic
<i>N</i>
‐Sulfonyl Ketimines and Alkynes
作者:Lin Dong、Chuan‐Hua Qu、Ji‐Rong Huang、Wei Zhang、Qian‐Ru Zhang、Jin‐Gen Deng
DOI:10.1002/chem.201303372
日期:2013.12.2
Atom‐economical addition: RhIII‐catalyzed “Grignard‐type” cyclization between cyclic N‐sulfonyl ketimines and internal alkynes has been developed to afford multifunctional spirocyclic sultam products in high yields (up to 99 %) under mild conditions (see scheme, Cp* = pentamethylcyclopentadienyl, DCE = 1,2‐dichloroethane).
Spirocyclic Sultam and Heterobiaryl Synthesis through Rh-Catalyzed Cross-Dehydrogenative Coupling of <i>N</i>-Sulfonyl Ketimines and Thiophenes or Furans
A useful approach is developed for the synthesis of various structurally interesting spirocyclic sultams and heterobiaryls using a cross-dehydrogenative coupling strategy that features high atom and step economy. This method employs [Cp*RhCl2]2 as a catalyst and N-sulfonylimine, a weak coordinating group, as an efficient directing group to assist C–H activation. A number of the coupled products were
Enantioselective Access to Spirocyclic Sultams by Chiral Cp<sup>x</sup>
-Rhodium(III)-Catalyzed Annulations
作者:Manh V. Pham、Nicolai Cramer
DOI:10.1002/chem.201504998
日期:2016.2.12
sultams are a valuable compound class in organic and medicinal chemistry. A rapid entry to this structural motif involves a [3+2] annulation of an N‐sulfonyl ketimine and an alkyne. Although the directing‐group properties of the imino group for C−H activation have been exploited, the developments of related asymmetric variants have remained very challenging. The use of rhodium(III) complexes equipped
Iridium-catalyzed direct C–H arylation of cyclic <i>N</i>-sulfonyl ketimines with arylsiloxanes at ambient temperature
作者:Writhabrata Sarkar、Arup Bhowmik、Sumit Das、Aiswarya Balaram Sulekha、Aniket Mishra、Indubhusan Deb
DOI:10.1039/d0ob01212b
日期:——
A highly efficient iridium-catalyzed ortho-selective C–H arylation of weakly coordinating cyclic N-sulfonyl ketimines has been achieved with environmentally benign aryl siloxanes at ambient temperature giving access to a novel class of biaryls.