Unique compounds functionalized with three-membered cyclic structures

Three-membered cyclic compounds are a fascinating class of compounds: they have the maximum torsional and angular strain (sp 3 hybridization but bond angles deviate from 109 o 28’), and possess unique physical and chemical properties. A lot of effort has been devoted to their synthesis and applications in recent years. This review provides an overview of various synthesis strategies for three-membered cyclic compounds, and summarizes the proposed reaction mechanisms and key issues such as structure-property relationships through specific examples. Meanwhile, the advantages and disadvantages of different synthesis strategies were discussed, including the recently developed electrochemical synthesis methods. Finally, the prospects and challenges for further scientific research and practical applications of three-membered cyclic compounds were emphasized. The summary of three-membered cyclic compounds is beneficial for the development and utilization of novel functionalized molecules. • Three-membered cyclic compounds possess the maximum torsional and angular strain. • These compounds include cyclopropyl, aziridine-, oxirane-based compounds, etc. • The design, properties, and application of these compounds were summarized.