Iron-Catalyzed Hydrogenation Reactions

The transition-metal-catalyzed hydrogenation of unsaturated organic compounds including alkenes, alkynes, aldehydes, ketones, and imines, is one of the most important organic transformations for both academic researches and industrial applications. The most popular catalysts for hydrogenation reactions are based on precious metals, such as rhodium, ruthenium, iridium, and palladium. The exhausting resource, the increasing high price, and the toxicity of the precious metals restrict their future applications. Iron is the most abundant transition metal in the earth crust and therefore the cheapest one with excellent environmental benign characters, is considered as an ideal replacement of the precious metal catalysts for hydrogenation reactions. This review paper introduced the newest achievements in the study of iron-catalyzed hydrogenation reactions in both homogenous and heterogeneous systems.