Since Adolf von Baeyer introduced the concept of "strain theory" in 1885 , ring strain energy (RSE) has been extensively studied to understand molecular reactivity. When atoms form a ring, the bond angles deviate from the natural bond angles found in acyclic molecules. This deviation in geometry leads to an increase in molecular energy, which can be characterized by the RSE . Highly strained molecules exist widely in nature, and provide unique challenges and unexpected opportunities for the development of new reactions and strategies . The release of RSE is a significant driving force for many chemical reactions and the design of novel synthesis methodologies . Highly strained molecules, such as cyclopropene derivatives, can be utilized for synthesizing wellcontrolled and sequence-regulated polymers by adjusting the ring strain through modulation of substituents . Less strained molecules, like cyclooctyne derivatives, can be tuned for multiple copper-free click reactions . Additionally, unusual ring structures, such as 1,2,3cyclohexatriene and its derivatives, can engage in a variety of reaction modes, enabling the novel synthesis of complex molecules .