Alkynes: Versatile Key Building Blocks for Constructing Fluorescent and Nonfluorescent Architectures through Click Chemistry

Abstract Alkynes are versatile and structurally distinctive functional groups widely employed in organic synthesis due to their linear geometry, orthogonal π-bonds, and unique reactivity. Their ability to participate in or undergo diverse organic transformations, including addition reactions, cycloadditions, and metal-catalyzed couplings, has made them key building blocks for constructing complex molecular architectures. Among these, the alkyne–azide click reactions are intriguing due to their ability to form complex architectures or frameworks such as branched or star-shaped molecules, macrocycles, and polymers. In this account, we highlight the contributions of our research group as well as some other similar works related to the design and synthesis of macrocycles, polymers, and branched molecules using mono- and di-functionalized alkynes and azides as rigid building blocks. Through the click reaction, we have synthesized a library of structurally well-defined fluorescent and nonfluorescent architectures. These systems showcase tunable optoelectronic and functional properties, underscoring their potential for a wide range of materials and biological applications.