Search results for "iron catalysis"
showing 5 items of 5 documents
Sequential Iron-Catalyzed C(sp2)–C(sp3) Cross-Coupling of Chlorobenzamides/Chemoselective Amide Reduction and Reductive Deuteration to Benzylic Alcoh…
2023
Benzylic alcohols are among the most important intermediates in organic synthesis. Recently, the use of abundant metals has attracted significant attention due to the issues with the scarcity of platinum group metals. Herein, we report a sequential method for the synthesis of benzylic alcohols by a merger of iron catalyzed cross-coupling and highly chemoselective reduction of benzamides promoted by sodium dispersion in the presence of alcoholic donors. The method has been further extended to the synthesis of deuterated benzylic alcohols. The iron-catalyzed Kumada cross-coupling exploits the high stability of benzamide bonds, enabling challenging C(sp2)–C(sp3) cross-coupling with alkyl Grign…
Iron-Catalyzed C–O Bond Activation: Opportunity for Sustainable Catalysis
2017
Oxygen-based electrophiles have emerged as some of the most valuable cross-coupling partners in organic synthesis due to several major strategic and environmental benefits such as abundance and potential to avoid toxic halide waste. In this context, iron-catalyzed C–O activation/cross-coupling holds particular promise to achieve sustainable catalytic protocols due to its natural abundance, inherent low toxicity, an excellent economic and ecological profile. Recently, tremendous progress has been achieved in the development of new methods for functional group tolerant iron-catalyzed cross-coupling reactions by selective C–O cleavage. These methods establish highly attractive alternatives to …
Iron‐Catalyzed Cross‐Couplings in the Synthesis of Pharmaceuticals: In Pursuit of Sustainability
2018
The scarcity of precious metals has led to the development of sustainable strategies for metal-catalyzed cross-coupling reactions. The establishment of new catalytic methods using iron is attractive owing to the low cost, abundance, ready availability, and very low toxicity of iron. In the last few years, sustainable methods for iron-catalyzed cross-couplings have entered the critical area of pharmaceutical research. Most notably, iron is one of the very few metals that have been successfully field-tested as highly effective base-metal catalysts in practical, kilogram-scale industrial cross-couplings. In this Minireview, we critically discuss the strategic benefits of using iron catalysts a…
N-Methylcaprolactam as a Dipolar Aprotic Solvent for Iron-Catalyzed Cross-Coupling Reactions: Matching Efficiency with Safer Reaction Media
2019
Although iron‐catalysis provides a powerful alternative to the more conventional palladium and nickel in the cross‐coupling arena, the major limitation is the necessity for carcinogenic N‐methylpyrrolidone as a co‐solvent in the vast majority of catalytic reactions. Herein, we introduce N‐methylcaprolactam as an efficient, non‐toxic and practical dipolar aprotic solvent for iron‐catalyzed C(sp2)−C(sp3) alkylative cross‐coupling of aryl chlorides and tosylates. The utility of this method is reflected by its wide substrate scope, high yields and capacity to cross‐couple challenging alkyl organometallics prone to b‐hydride elimination and homocoupling. Considering the broad utility of iron‐cat…
Iron‐Catalyzed C(sp2)−C(sp3) Cross‐Coupling of Chlorobenzamides with Alkyl Grignard Reagents: Development of Catalyst System, Synthetic Scope, and Ap…
2019
Direct preparation of alkylated amide‐derivatives by cross‐coupling chemistry using sustainable protocols is challenging due to sensitivity of the amide functional group to reaction conditions. Herein, we report the synthesis of alkyl‐substituted amides by iron‐catalyzed C(sp2)−C(sp3) cross‐coupling of Grignard reagents with aryl chlorides. The products of these reactions are broadly used in the synthesis of pharmaceuticals, agrochemicals and other biologically‐active molecules. Furthermore, amides are used as versatile intermediates that can participate in the synthesis of valuable ketones and amines, providing access to motifs of broad synthetic interest. The reaction is characterized by …