The Thorpe-Ingold effect and its advances in both theoretical and experimental studies are introduced briefly. Its recent applications in cyclizations for formations of three-, four-, five-, and six-membered ring products are reviewed. The Thorpe-Ingold effect can promote intra- and intermolecular cyclizations effectively, accelerating reaction rates and improving yields in cyclizations. The effect exerts its influence in reactions through steric hindrance and/or electronic effect and is impacted by catalysts and solvents in some cases. Application of the effect can help some difficult cyclization reactions to occur smoothly, affording the desired products in good yields.

Contents
1 Thorpe-Ingold effect
2 Application in cyclizations involving formations of three-membered ring products
2.1 Cyclopropane derivatives
2.2 Ethylene oxide derivatives
3 Application in cyclizations involving formations of four-membered ring products
3.1 Cyclobutane deivatives
3.2 Oxacyclobutane derivatives
4 Application in cyclizations involving formations of five-membered ring products
4.1 Cyclopentane derivatives
4.2 Azacyclopentane derivatives
4.3 Oxacyclopentane derivatives
4.4 Thiazolidine derivatives
4.5 Phosphacyclopentane derivatives
4.6 Silicacyclopentane derivatives
5 Application in cyclizations involving formations of six-membered ring products
5.1 Cyclohexane derivatives
5.2 Azacyclohexane derivatives
5.3 Oxacyclohexane derivatives
5.4 Silicacyclohexane derivatives
6 Miscellaneous
7 Summary and prospects