Traceless Benzylic C−H Amination via Bifunctional
<i>N</i>
‐Aminopyridinium Intermediates
作者:Pritam Roychowdhury、Roberto G. Herrera、Hao Tan、David C. Powers
DOI:10.1002/anie.202200665
日期:2022.7.11
C−Hamination chemistry viatracelessbifunctional nitrogen activation is reported. Sequential C−H aminopyridylation followed by Ni-catalyzed cross-coupling with aryl boronic acids affords the products of aryl nitrene insertion into C−H bonds. These products are unavailable by direct nitrene insertion due to the intrinsic instability of aryl nitrenes. The described method can be applied in the context
We report herein the synthesis of new glycoporphyrin ligands which bear a glucopyranoside derivative on each meso-aryl moiety of the porphyrin skeleton. The saccharide unit is directly conjugated to the porphyrin or a triazole spacer is placed between the carbohydrate and porphyrin ring. The obtained glycoporphyrin ligands were employed to synthesize cobalt(II), ruthenium(II), and iron(III) complexes which were tested as catalysts of C-H bond aminations by organic azides. Two of the synthesized complexes were very efficient in promoting catalytic reactions, and the results achieved indicated that ruthenium and iron complexes show an interesting complementary catalytic activity in several amination reactions. The eco-friendly iron catalyst displayed very good chemical stability in catalyzing the amination reaction for three consecutive runs without losing catalytic activity.
An Effective [Fe<sup>III</sup>(TF<sub>4</sub>DMAP)Cl] Catalyst for C–H Bond Amination with Aryl and Alkyl Azides
作者:Yi-Dan Du、Zhen-Jiang Xu、Cong-Ying Zhou、Chi-Ming Che
DOI:10.1021/acs.orglett.8b03765
日期:2019.2.15
[FeIII(TF4DMAP)Cl] can efficiently catalyzeintermolecular sp3 C–Hamination using aryl azides and intramolecular sp3 C–Hamination of alkyl azides in moderate-to-high product yields. At catalyst loading down to 1 mol %, the reactions display high chemo- and regioselectivity with broad substrate scope and are effective for late-stage functionalization of complex natural/bioactive molecules.