Coupling reactions form an important class of reactions in organic synthesis and these reactions are usually catalysed by metals and are of great significance. Copper due to its versatility and low toxicity has always gained much attention. This first review on copper‐catalysed amination of aryl and heteroaryl halides summarises the developments in this area and covers literature upto 2019.

Manganese‐catalysed reactions have attracted great attention recently due to the high relative abundance and cheap and eco‐friendly behaviour. Applications of manganese catalysis in cross‐dehydrogenative coupling are among the hottest areas since 90% of the contributions are very recent. Dehydrogenation of alcohols using Mn‐pincer systems is highly explored nowadays for cross‐coupling to synthesise a variety of products and Mn‐catalysed C−H activation, and radical reactions are applied in dehydrogenative couplings of various synthons. This review focuses on the synthesis of synthetically as well as biologically important motifs such as carbonyl compounds, olefins, nitrogen heterocycles, amines, imines, etc. using manganese‐catalysed dehydrogenative cross‐coupling reactions.

Nickel-catalyzed C–H activation has become a predominant and ubiquitous research area in organic chemistry.

The asymmetricM annichr eactioni savery important method for CÀCb ond formation,a nd it is the classical method for the preparation of b-amino ketones and aldehydes. The resulting b-amino carbonyl compounds are widely found in nature, which attests to the importance of this reaction. This Focus Review providesa no verview of asymmetricM annich reactions, the various catalysts that have been used, and its applications,f or papers published since 2013. Scheme1.The Mannich reaction.Scheme2.The mechanism of the Mannich reaction;reproduced with permissionfrom Ref.[1]. andhi University. His research interests are in the areaso fo rganic synthesis, medicinal chemistry,a nd catalysis, in particularr uthenium-, iron-, zinc-, and copper-catalyzedr eactions. His h-index is 24.