RESUMO
In recent years, transition-metal-catalyzed C-H functionalization has gradually developed into a powerful tool for the synthesis of ferrocenes in an atom- and step-economic fashion. However, despite significant achievements, the vast majority of these C-H functionalizations required precious 4d or 5d transition metal catalysts. The use of inexpensive and sustainable 3d metals in the C-H functionalization of ferrocenes remains challenging, especially the development of asymmetric versions. Herein, we summarize the remarkable recent progress in the synthesis of ferrocenes by 3d transition metal-catalyzed C-H activation until December 2021.
Assuntos
Elementos de Transição , Catálise , Metalocenos , MetaisRESUMO
Dibenzocyclooctadiene lignans are an interesting class of molecules because of their unique structure based on an axially chiral biaryl moiety as well as their significant biological activity. Herein, we describe the development of a palladium-catalyzed atroposelective C-H alkynylation and its application in gram-scale, stereocontrolled formal syntheses of (+)-isoschizandrin and (+)-steganone. tert-Leucine was identified as an efficient, catalytic transient chiral auxiliary. A wide range of enantiomerically enriched biaryl compounds were prepared by this approach in good yields (up to 99 %) with excellent enantioselectivity (up to >99 %â ee).
RESUMO
We report here strategic functionalization of the FDA approved chelator deferasirox (1) in an effort to produce organelle-targeting iron chelators with enhanced activity against A549 lung cancer cells. Derivative 8 was found to have improved antiproliferative activity relative to 1. Fluorescent cell imaging revealed that compound 8 preferentially localises within the lysosome.
Assuntos
Antineoplásicos/farmacologia , Deferasirox/farmacologia , Quelantes de Ferro/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Organelas/química , Células A549 , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Deferasirox/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Quelantes de Ferro/química , Neoplasias Pulmonares/diagnóstico por imagem , Lisossomos/química , Microscopia Confocal , Estrutura Molecular , Imagem ÓpticaRESUMO
The amide-directed cobalt(III)-catalyzed C-H amidation of ferrocene carboxamides using 1,4,2-dioxazol-5-ones as robust and efficient amidating reagents has been developed. This reaction proceeds efficiently under mild reaction conditions with good functional group tolerance, providing expedient access to a broad range of ferrocenes containing a nitrogen group on the Cp ring.
RESUMO
Cp*Cobalt(III)-catalyzed enantioselective C-H amidation of ferrocenes using monoprotected amino acids (MPAAs) as chiral ligands was developed. The reaction was performed under mild conditions in high yields (up to 97%) with moderate enantioselectivity (up to 77.5:22.5 er), providing a promising strategy to create planar chirality via base-metal-catalyzed enantioselective C-H activation.
RESUMO
The Ru-catalyzed meta-C-H benzylation of arenes bearing pyridyl, pyrimidyl, and pyrazolyl directing groups with toluene derivatives has been reported. Heptafluoroisopropyl iodide (iC3F7I) was employed as both a mild oxidant and radical initiator. This reaction showed excellent site-selectivity and tolerated a wide range of functional groups, providing a new strategy for the synthesis of various diarylmethane moieties.