Dear Colleagues,

Cycloaddition reactions describe the formation of two single bonds between two independent unsaturated molecules, resulting in the formation of new cyclic compounds with different ring sizes. Cycloaddition reactions are considered among the most powerful bond-forming reactions in organic synthesis because of their ability to form many bonds in a single step and several stereogenic centers can be generated at the same time with predictable stereochemical outcomes. A cycloaddition reaction is categorized as a [m + n] cycloaddition when a system of m conjugated atoms combines with a system of n conjugated atoms. There are many examples of cycloaddition reactions, including Diels–Alder reactions or [4+2] cycloaddition reactions; [3+2] cycloaddition reactions; [2+2] cycloaddition reactions; formal [3+3] cycloaddition reactions; [5+1] cycloaddition reactions form biologically active 6-membered; 5-membered; and 4-membered rings, respectively, and higher order cycloaddition reactions. Additionally, hetero-Diels–Alder reactions allow the formation of six-membered rings by the interaction of heterodienes and/or ethylenes. Cycloaddition reactions are considered as advanced methods used to construct and develop new functional material in the modern synthesis of natural products and biologically active substances with different applications in pharmaceuticals, chemical research and materials. Cycloaddition reactions can take place either through metal catalysis or free metal catalysis. Molecular electron density theory (MEDT) has been recently hypothesized to explain the reaction mechanism of the cycloaddition reactions.

Prof. Dr. Assem Barakat
Prof. Dr. Luis R. Domingo
Guest Editors

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• cycloaddition reaction
• molecular electron density theory (MEDT)
• Diels–Alder/hetero-Diels–Alder reactions
• [3+2] cycloaddition reactions
• [2+2] cycloaddition reactions
• [5+1] cycloaddition reactions
• [5+2] cycloaddition reactions
• formal [3+3] cycloaddition reactions
• higher order of cycloaddition reactions
• staudinger ketene-imine cycloaddition
• asymmetric synthesis
• metal catalyzed cycloaddition reactions
• enantioselective cycloaddition reactions
• fused heterocycles
• spiro-compounds
• natural products by cycloaddition reactions
• anti-viral compounds by cycloaddition reactions
• biological activity
• material chemistry by cycloaddition reactions
• drug delivery and cycloaddition reactions
• computational study
• theoretical calculations