Iron Catalysis in Organic Synthesis

Efficient, selective and sustainable catalysis of carbon dioxide

Ionic liquid with acidic properties is an important branch in the wide ionic liquid field and the aim of this article is to cover all aspects of these acidic ionic liquids, especially focusing on the developments in the last four years. The structural diversity and synthesis of acidic ionic liquids are discussed in the introduction sections of this review. In addition, an unambiguous classification system for various types of acidic ionic liquids is presented in the introduction. The physical properties including acidity, thermo-physical properties, ionic conductivity, spectroscopy, and computational studies on acidic ionic liquids are covered in the next sections. The final section provides a comprehensive review on applications of acidic ionic liquids in a wide array of fields including catalysis, CO2 fixation, ionogel, electrolyte, fuel-cell, membrane, biomass processing, biodiesel synthesis, desulfurization of gasoline/diesel, metal processing, and metal electrodeposition.

Acidic Ionic Liquids.

Sustainable conversion of carbon dioxide: the advent of organocatalysis

Sustainable metal-based catalysts for the synthesis of cyclic carbonates containing five-membered rings

Carbon Dioxide in Heterocyclic Synthesis

The polyethylene glycol-functionalized basic ionic liquid TBDP is found to be a highly efficient and recyclable catalyst for the synthesis of cyclic carbonates (III) via direct carboxylation of epoxides (I) without the need of any organic solvents or additives.

Highly Efficient Conversion of Carbon Dioxide Catalyzed by Polyethylene Glycol-Functionalized Basic Ionic Liquids.

Reduction of Carbon Dioxide to Energy-Rich Products

An iron(III)-catalyzed three-component coupling reaction of alkynes, CH2Cl2 and amines was developed for facile synthesis of propargylamines. Preliminary mechanism investigation using in situFT-IR reveals that the crucial Fe-acetylide intermediate could be formed through C–H bond activation of alkynes thanks to cooperative effect of FeCl3 and 1,1,3,3-tetramethylguanidine.

Efficient Iron(III)‐Catalyzed Three‐Component Coupling Reaction of Alkynes, CH2Cl2 and Amines to Propargylamines.

An easily prepared Fe(III)-derived Lewis acid ionic liquid ([C4mim][FeCl4]), being comprised of 1-butyl-3-methyl imidazolium cation and tetrachloroferrate anion, was found to be an efficient, recyclable catalyst for benzylation of various arenes/heteroarenes into the diarylmethanes derivatives under mild reaction conditions without utilization of additional organic solvent. Interestingly, the acidity of [C4mim][FeCl4] could account for its catalytic activity in promoting the Lewis acid-catalyzed alkylation. Notably, this type of Fe(III)-based ionic liquid (IL) shows excellent stability, and could be easily recovered, and reused for five times without significant loss of its catalytic activity.

Jian Gao

Papers

Carbon Dioxide in Heterocyclic Synthesis

Highly Efficient Conversion of Carbon Dioxide Catalyzed by Polyethylene Glycol-Functionalized Basic Ionic Liquids.

Reduction of Carbon Dioxide to Energy-Rich Products

Efficient Iron(III)‐Catalyzed Three‐Component Coupling Reaction of Alkynes, CH2Cl2 and Amines to Propargylamines.

Iron(III)-Based Ionic Liquid-Catalyzed Regioselective Benzylation of Arenes and Heteroarenes.