Mechanistic insights from theory on the reduction of CO2, N2O, and SO2 molecules using tripodal diimine-enolate substituted magnesium(i) dimers

Low oxidation state and hydrido group 2 complexes: synthesis and applications in the activation of gaseous substrates

Numerous industrial processes utilise gaseous chemical feedstocks to produce useful chemical products. Atmospheric and other small molecule gases, including anthropogenic waste products (e.g. carbon dioxide), can be viewed as sustainable building blocks to access value-added chemical commodities and materials. While transition metal complexes have been well documented in the reduction and transformation of these substrates, molecular complexes of the terrestrially abundant alkaline earth metals have also demonstrated promise with remarkable reactivity reported towards an array of industrially relevant gases over the past two decades. This review covers low oxidation state and hydrido group 2 complexes and their role in the reduction and transformation of a selection of important gaseous substrates towards value-added chemical products.

Cooperative small molecule activation by apolar and weakly polar bonds through the lens of a suitable computational protocol

Small molecule activation processes are central in chemical research and cooperativity is a valuable tool for the fine-tuning of the efficiency of these reactions. In this contribution, we discuss recent and remarkable examples in which activation processes are mediated by bimetallic compounds featuring apolar or weakly polar metal-metal bonds. Relevant experimental breakthroughs are thoroughly analyzed from a computational perspective. We highlight how the rational and non-trivial application of selected computational approaches not only allows rationalization of the observed reactivities but also inferring of general principles applicable to activation processes, such as the breakdown of the structure-reactivity relationship in carbon dioxide activation in a cooperative framework. We finally provide a simple yet unbiased computational protocol to study these reactions, which can support experimental advances aimed at expanding the range of applications of apolar and weakly polar bonds as catalysts for small molecule activation.

Exploring the reactivity of homoleptic organozincs towards SO2: Synthesis and structure of a homologous series of organozinc sulfinates

Studies on the reactivity of zinc alkyl compounds towards SO2 are relatively less explored than either the oxygenation or hydrolysis reactions. We report on environmentally friendly and efficient syntheses of...

Activation of Small Molecules (H2, CO2, N2O, CH4, and C6H6) by a Porphyrinoid-Based Dimagnesium(I) Complex, an Electride

A density functional theory-based computation has been carried out to reveal the geometrical and electronic structures of Mg₂EP (1), where EP is an extended (3.1.3.1) porphyrinoid system. EP is a 22 π electronic system and is aromatic in nature. Here, we have studied the thermodynamic and kinetic stabilities of EP^2--supported Mg₂ ²⁺ ion. The nature of bonding has been studied using natural bond orbital and atoms in molecule schemes. The presence of a covalent Mg(I)-Mg(I) σ-bond in Mg₂EP is confirmed. The occurrence of a non-nuclear attractor (NNA) with large electron population, negative Laplacian of electron density at NNA, and presence of an electron localization function basin along with large nonlinear optical properties prompt us to classify Mg₂EP as the first porphyrinoid-based organic electride. Further five small molecules, viz., dihydrogen (H₂), carbon dioxide (CO₂), nitrous oxide (N₂O), methane (CH₄), and benzene (C₆H₆), are found to be activated by the electron density between the two Mg atoms in Mg₂EP.