Recent development in iron- and manganese-catalysed hydrosilylation: unravelling diverse structures of complexes and mechanisms

The emerging field of organometallic catalysis has turned toward first-row transition metals due to their greater abundance, lower cost, and unique reactivity profiles. Among these, iron and manganese, as the most abundant transition metals in the Earth's crust, have emerged as promising alternatives to precious metals in catalytic applications. Over the past half-decade, (2019 to present), there has been significant progress in Fe- and Mn-catalysed hydrosilylation reactions involving unsaturated bonds such as CC, CC, CO, and CN. This perspective provides a comprehensive summary of recent developments in the hydrosilylation of alkenes, alkynes, carbonyl compounds, and nitrogen-containing substrates, catalysed by various well-defined Fe and Mn complexes. It highlights not only the synthetic scope of these transformations but also the mechanistic insights that govern their reactivity. Particular emphasis is placed on the impact of ligands (P-, N-, and C-donors) on catalytic performance, as well as comparisons with structurally related polydentate ligand systems. The analysis further explores how variations in ligand architecture influence both catalytic activity and selectivity. This perspective ultimately aims to provide valuable guidance for future catalyst and ligand design, thereby advancing sustainable and efficient catalytic processes using base metals.