Recent Developments on the Earth-Abundant-Metal-Catalyzed α,β-Dehydrogenation of Carbonyl Compounds

α,β-Unsaturated carbonyl compounds are versatile building blocks in modern organic synthetic chemistry. In recent decades, various approaches have been established to access to these products, such as halogenation-dehydrohalogenation methods, organosulfur methods, organoselenium methods, earth-abundant-metal-catalyzed methods, precious-metal-catalyzed methods, and metal-free methods, etc. Among these, earth-abundant-metal-catalyzed methods (i.e., iron, cobalt, nickel, copper) continue to attract the attention of chemists because they are readily available, inexpensive, and environmentally friendly. Presently, there are only a few reviews covering earth-abundant- metal-catalyzed α,β-dehydrogenations. Hence, the aim of this short review is to provide a detailed update on the recent developments on earth-abundant-metal-catalyzed α,β-dehydrogenations of carbonyl compounds. 1 Introduction 2 Iron-Catalyzed Dehydrogenation 3 Cobalt-Catalyzed Dehydrogenation 4 Nickel-Catalyzed Dehydrogenation 5 Copper-Catalyzed Dehydrogenation 6 Conclusion.