The article discusses the importance of carbon dioxide (CO₂) as a renewable one-carbon (C1) building block in organic synthesis, highlighting its potential for sustainable resource management. It reviews recent advances in the catalytic valorization of CO₂, focusing on its activation and application in organic synthesis under mild conditions. CO₂ is a stable, thermodynamically inert molecule, but its reactivity with strong nucleophiles allows for the formation of C-C and C-H bonds. Various catalytic systems, including metalloporphyrins, salen complexes, and bimetallic catalysts, have been developed to facilitate CO₂ fixation, particularly in the synthesis of cyclic carbonates and polycarbonates from epoxides. These processes are atom-economical and have been industrialized for the production of materials such as ethylene and propylene carbonates. The article also explores other CO₂ activation strategies, such as reductive formylation and methylation of amines, which involve the use of amines to lower the activation energy of CO₂. These methods enable the formation of C-N bonds and the production of valuable methylamines. Additionally, oxidative cyclometallation with low-valent nickel and palladium complexes has been used to couple CO₂ with unsaturated hydrocarbons, enabling the formation of C-C bonds. Carboxylation reactions via CO₂ insertion into C-M bonds have also been studied, with the use of transition metal catalysts to facilitate the reaction. The article further discusses the in situ generation of CO from CO₂, which can be used in carbonylation reactions to produce value-added chemicals. This approach is more sustainable and safer than using CO directly. Photocatalytic methods for CO₂ reduction to CO are also highlighted, with the development of efficient systems that use visible light and sacrificial electron donors to generate CO. Overall, the review emphasizes the importance of CO₂ valorization in sustainable chemistry, highlighting the need for efficient catalysts, milder reaction conditions, and broader substrate scope to enhance the practical application of CO₂ in organic synthesis. The development of new catalytic systems and the exploration of alternative reduction methods are crucial for the future of CO₂ utilization in chemical processes.The article discusses the importance of carbon dioxide (CO₂) as a renewable one-carbon (C1) building block in organic synthesis, highlighting its potential for sustainable resource management. It reviews recent advances in the catalytic valorization of CO₂, focusing on its activation and application in organic synthesis under mild conditions. CO₂ is a stable, thermodynamically inert molecule, but its reactivity with strong nucleophiles allows for the formation of C-C and C-H bonds. Various catalytic systems, including metalloporphyrins, salen complexes, and bimetallic catalysts, have been developed to facilitate CO₂ fixation, particularly in the synthesis of cyclic carbonates and polycarbonates from epoxides. These processes are atom-economical and have been industrialized for the production of materials such as ethylene and propylene carbonates. The article also explores other CO₂ activation strategies, such as reductive formylation and methylation of amines, which involve the use of amines to lower the activation energy of CO₂. These methods enable the formation of C-N bonds and the production of valuable methylamines. Additionally, oxidative cyclometallation with low-valent nickel and palladium complexes has been used to couple CO₂ with unsaturated hydrocarbons, enabling the formation of C-C bonds. Carboxylation reactions via CO₂ insertion into C-M bonds have also been studied, with the use of transition metal catalysts to facilitate the reaction. The article further discusses the in situ generation of CO from CO₂, which can be used in carbonylation reactions to produce value-added chemicals. This approach is more sustainable and safer than using CO directly. Photocatalytic methods for CO₂ reduction to CO are also highlighted, with the development of efficient systems that use visible light and sacrificial electron donors to generate CO. Overall, the review emphasizes the importance of CO₂ valorization in sustainable chemistry, highlighting the need for efficient catalysts, milder reaction conditions, and broader substrate scope to enhance the practical application of CO₂ in organic synthesis. The development of new catalytic systems and the exploration of alternative reduction methods are crucial for the future of CO₂ utilization in chemical processes.