Abstract Cycloadditions, annulations, electrocyclic reactions, and cyclizations are organic reactions for construction of cyclic organic compounds. They describe different types of organic reactions completely. However, they have been misused and applied randomly sometimes. This article expounds the different characteristics of these four types of organic reactions, hoping to teach them accurately in university course and to establish the exact concepts and definations for future workers on organic chemistry at their beginning.
XU Jia-Xi, CHEN Ning. Differentiation of Cycloaddition, Annulation, Electrocyclic Reaction, and Cyclization[J]. Chinese Journal of Chemical Education, 2022, 43(4): 112-116.