The past decade has witnessed staggering progress in the chemistry of compounds with low‐valent main‐group elements. Although these discoveries are mostly fundamental by nature, these compounds show promising reactivity towards small molecule activation. The reactivity of these compounds stems from the modest HOMO–LUMO energy gap; a characteristic known for the transition metals. The journey began in 2005 with the facile activation of dihydrogen by an alkyne analog of germanium [ArGe≡GeAr; Ar=2,6‐Trip2‐C6H3 (Trip=2,4,6‐iPr3‐C6H2)]. Subsequently, tremendous progress has been achieved in understanding and elucidating the potential of these compounds to activate small molecules as well as to use them in a variety of stoichiometric and catalytic transformations. In this review, we focus on developments in the activation of H2, NH3, CO, and CO2 by compounds with multiply bound or open shell main‐group elements. Emphasis will be given to their catalytic activity.

A benz-amidinato calcium compound, [PhC(NiPr)CaI] (1), catalyzed hydroboration of a wide range of aldehydes and ketones using pinacolborane (HBpin) at room temperature is reported. The catalyst shows functional group tolerance even towards OH and NH groups. The strategy was further extended to imines.

Ever increasing demand for green and sustainable chemical processes has set up a drive to replace transition metals with earth-abundant, nontoxic, and environmentally benign alternatives. In this regard, the alkaline earth metal complexes have attracted significant attention. Herein, we have used a β-diketiminato ligand with methyl-pyridine side arm to synthesize magnesium (1) and calcium (2) compounds. The constitutions of 1 and 2 have been confirmed by single crystal X-ray studies, which show that the magnesium and calcium atom in 1 and 2 possesses octahedral geometry. Subsequently, we have used them as catalysts (1 mol %) for hydroboration of a wide range of aldehydes using pinacolborane (HBpin) at room temperature. The strategy has further been extended to ketones with 2 mol % catalyst loading. DFT calculations have been performed to understand the mechanism.

Readily accessible lithium compounds have been employed to catalyze the hydroboration of alkene and alkynes including terpenes using HBpin with anti-Markovnikov selectivity. The mechanism is proposed on the basis of experimental and DFT studies.