Expedient Iron-Catalyzed C−H Allylation/Alkylation by Triazole Assistance with Ample Scope
作者:Gianpiero Cera、Tobias Haven、Lutz Ackermann
DOI:10.1002/anie.201509603
日期:2016.1.22
for the iron‐catalyzed C−H allylation of arenes, heteroarenes, and alkenes with ample scope. The versatile catalyst also proved competent for site‐selective methylation, benzylation, and alkylation with challenging primary and secondary halides. Triazole‐assisted C−H activation proceeded chemo‐, site‐, and diastereo‐selectively, and the modular TAM directing group was readily removed in a traceless
Iron‐Electrocatalyzed C−H Arylations: Mechanistic Insights into Oxidation‐Induced Reductive Elimination for Ferraelectrocatalysis
作者:Cuiju Zhu、Maximilian Stangier、João C. A. Oliveira、Leonardo Massignan、Lutz Ackermann
DOI:10.1002/chem.201904018
日期:2019.12.18
precious 5d and 4d transition metals, such as iridium, palladium and rhodium. In contrast, the unique potential of less toxic Earth-abundant 3d metals has been underexplored. While iron is the most naturally abundant transition metal, its use in oxidative, organometallic C-H activation has faced major limitations due to the need for superstoichiometric amounts of corrosive, cost-intensive DCIB as the
Iron-Catalyzed C(sp<sup>2</sup>)H and C(sp<sup>3</sup>)H Methylations of Amides and Anilides
作者:Karolina Graczyk、Tobias Haven、Lutz Ackermann
DOI:10.1002/chem.201501134
日期:2015.6.8
bioactivities and physical properties of pharmacologically active drugs. Direct introduction of the methyl group by CH activation was accomplished with a versatile iron catalyst, which enabled the CH methylation of (hetero)benzamides, anilides, alkenes, and even alkanes by triazoleassistance in a chemo‐, site‐ and diastereo‐selective fashion.
Versatile palladium-catalyzed CH arylations of benzamides were accomplished by triazole amine (TAM) assistance. The robustness of the palladium-catalyzed CH functionalization protocol was reflected by its broad functional group tolerance, ample substrate scope and CH arylations under silver-free reaction conditions.
Silver-Free Palladium-Catalyzed sp<sup>3</sup> and sp<sup>2</sup> C–H Alkynylation Promoted by a 1,2,3-Triazole Amine Directing Group
作者:Xiaohan Ye、Chang Xu、Lukasz Wojtas、Novruz G. Akhmedov、Hao Chen、Xiaodong Shi
DOI:10.1021/acs.orglett.6b01319
日期:2016.6.17
Triazole amine was identified as an effective directing group in promoting C-H alkynylation under silver-free conditions. No other external oxidant was required, and the alkynylation products were received in good to excellent yields. X-ray crystallographic analysis confirmed a direct C-H activation intermediate. Other typical directing groups, including pyridine amine (PIP) and 8-aminoquinoline (QA), gave almost no reaction under identical conditions, which highlighted the unique reactivity of the triazole directing group in direct C-H functionalization.