In view of the growing environmental concerns and the need to involve alternative sources of raw materials in the chemical industry, intensive research efforts in the last decades have focused on carbon dioxide reactions. In this context, the present review discusses prior studies that were aimed at producing commercially important compounds, such as acids, alcohols, organic carbonates, and polycarbonates, in homogeneous catalytic systems that contain transition-metal complexes. Such systems have been traditionally valued for their high activity and selectivity under relatively mild conditions. The review provides systematized information both on CO₂ reactions with hydrogen to produce C₁ chemicals such as formic acid and methanol, and on CO₂ interactions with organics (e.g., olefins, alcohols, and epoxides) to produce valuable chemical compounds.

A novel method for the synthesis of 2-ethyl-1,3-dioxolane and related short-chain acetals by tandem hydroformylation–acetalization of ethylene is described. The reaction occurs in a biphasic system. The polar phase contains a catalytic system (Rh/TPPTS/H⁺), which is easy to separate and remains active when reused. Under optimized conditions the hydroformylation TOF reaches 1520 h⁻¹ with an acetal selectivity of 90%. How the pH value, temperature, solvent and structure of the starting polyols influence the efficiency and selectivity of the tandem reaction is shown.

Due to their unique structural and mechanical characteristics, zeolites are of great interest as carriers for the design of catalysts. This review is focused on the progress in the development of new zeolite-based catalysts for hydroformylation. The procedures of materials synthesis and modification, the methods of metal introduction, and the effect of the catalyst structure on the activity, selectivity, and stability of the hydroformylation catalysts are discussed. This review highlights the role of up-to-date analytical techniques in the development of fine-tuned active and selective hydroformylation catalysts. The greatest achievements over the past five years considered in detail in this review demonstrate a high potential of zeolite-based hydroformylation catalysts. Future prospects and possible directions of upcoming studies are regarded.

Three rhodium-containing catalytic systems active in tandem hydroformylation/hydrogenation of unsaturated substrates were developed based on polyethyleneimine (PEI): a homogeneous system with distillation of the product; a biphasic system with segregation of the product and catalyst into a non-polar phase and a polar phase, respectively; and a solid catalyst prepared from PEI and (3-chloropropyl)triethoxysilane with its centrifugation from the product mixture. All the systems were shown to be reusable over multiple cycles in hydroformylation/hydrogenation, with the catalytic activity being partially sustained in both steps of the tandem process. Methylation of PEI (or its NH and NH₂ moieties in the case of solid material) was found to be critical for the catalytic activity in hydroformylation.