An efficient, iron-catalyzed C-H alkylation of benzothiazoles by using alkyl diacyl peroxides and alkyl tert-butyl peresters which are readily accessible from carboxylic acids to synthesize 2-alkylbenzothiazoles is developed. This reaction is environmentally benign and compatible with a broad range of functional groups. Various primary, secondary, and tertiary alkyl groups can be efficiently incorporated into diverse benzothiazoles. The effectiveness of this method is illustrated by late-stage functionalization of biologically active heterocycles.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/acs.orglett.6b03287 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Mechanistic Studies and Identification of Catalyst Deactivation Pathways for Pyridine(diimine) Iron Catalyzed C(sp)-H Borylation.
ACS Catal
September 2024
Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States.
The synthesis and application of aryl-substituted pyridine(diimine) iron complexes (PDI)FeCH to the catalytic borylation of heteroarenes under thermal conditions is described. Improvements in catalyst design and performance were guided by precatalyst activation studies, where investigations into stoichiometric reactivities of iron borohydride (4- Bu- PDI)Fe(HBPin) and iron furyl (4- Bu- PDI)Fe(2-methylfuryl) complexes revealed facile C(sp)-H activation and a slower and potentially turnover-limiting C(sp)-B formation step. Formation of the flyover dimer, [(4- Bu- PDI)Fe] was identified as a catalyst deactivation pathway and formally iron(0) complexes were found to be inactive for borylation.
View Article and Find Full Text PDFLate-Stage Radical C-H Alkylamination of Tyrosine Compounds and Phenol-Containing Drugs.
Org Lett
October 2024
University of the Basque Country (UPV/EHU), Department of Organic Chemistry I, Joxe Mari Korta R&D Center, Avda. Tolosa 72, 20018 Donostia-San Sebastián, Spain.
A modular site-selective iron-catalyzed radical amination of a number of phenol-containing biomolecules such as tyrosine-containing peptides, estrogens, and other phenol-based pharmaceuticals has been developed. The method features the use of the cost-efficient combination of FeBr as catalyst along with triflic acid as Brønsted acid, thereby enabling the predictable appendance of morpholine and related heterocycles at the C-H bond of phenols in a late-stage fashion.
View Article and Find Full Text PDFIntramolecular C-H Oxidation in Iron(V)-oxo-carboxylato Species Relevant in the γ-Lactonization of Alkyl Carboxylic Acids.
ACS Catal
September 2024
Institut de Química Computacional i Catàlisi (IQCC), Departament de Química, Universitat de Girona, C/Ma Aurèlia Capmany 69, 17003 Girona, Catalonia, Spain.
High-valent oxoiron species have been invoked as oxidizing agents in a variety of iron-dependent oxygenases. Taking inspiration from nature, selected nonheme iron complexes have been developed as catalysts to elicit C-H oxidation through the mediation of putative oxoiron(V) species, akin to those proposed for Rieske oxygenases. The addition of carboxylic acids in these iron-catalyzed C-H oxidations has proved highly beneficial in terms of product yields and selectivities, suggesting the direct involvement of iron(V)-oxo-carboxylato species.
View Article and Find Full Text PDFβ-Tryptophans by Iron-Catalyzed Enantioselective Amination of 3-Indolepropionic Acids.
Org Lett
October 2024
Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35043 Marburg, Germany.
A straightforward and general strategy for the catalytic asymmetric synthesis of β-tryptophans by carboxylic-acid-directed intermolecular C-H amination has been developed. The iron-catalyzed C-H amination of 3-indolepropionic acids with BocNHOMs (Boc, -butyloxycarbonyl; OMs, methylsulfonate) in the presence of the base piperidine provides N-Boc-protected β-tryptophans in a single step with high enantiomeric excess (ee) of up to >99%. Mechanistic experiments and density functional theory calculations support a mechanism through carboxylate-directed iron-mediated C(sp)-H nitrene insertion.
View Article and Find Full Text PDFIron-Catalyzed C-H Arylphosphorylation of Quinoxalines.
Org Lett
September 2024
Guangxi Colleges and Universities Key Laboratory of Applied Chemistry Technology and Resource Development, School of Chemistry and Chemical Engineering, Guangxi University, Nanning, Guangxi 530004, P. R. China.
A one-pot strategy for iron-catalyzed C2,3-H arylphosphorylation of electron-deficient quinoxalines with phosphines and aryl compounds is reported. The proposed method features the use of non-noble metal catalysts, the capacity of utilizing multiple aryl compounds as substrates, the simultaneous formation of C-P and C-C bonds in one pot, the simplicity of its operation, the mildness of the reaction conditions, and its compatibility with a wide range of substrates. Moreover, it offers a practical route for direct access to 2-aryl-3-phosphino -heteroarenes, a class of potential cyclometalated C^N and N^P bidentate ligands that are difficult to prepare with existing C(sp)-H functionalization methods.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!