Cyclic compounds undergoing reaction at a ring atom exhibit striking changes in reactivity with variation in ring size. These dHerences in chemical behavior have been attributed to the changes in internal strain in the cyclic structures which accompany changes in the coordination number of the ring atom undergoing reaction (I-strain). To test the validityof the interpretation, the 1-chloro-1-methylcycloalkanes with rings of 4-, 5-, 6-, 7-, 8-, 9-, IO-, 11-, ...
