The development of a type of these compounds, named as a variation on the name of these compounds, earned Jean-Marie Lehn the chemistry Nobel Prize in 1987, and those compounds can be considered three-dimensional analogues of the molecules for which Charles Pedersen shared that Nobel Prize. Agostic interactions can occur when these compounds contain a C-H bond. which are important when two of these compounds combine in a (*) migratory insertion. Preorganisation contributes to the increased stability with examples of these compounds such as crown ethers by the macrocyclic effect, which is stronger than the chelate effect. The indenyl effect (10[1])is explained by a change in hapticity from 5 to 3 in one of these compounds, and polydentate examples of them (10[1])include EDTA. (10[1])For 10 points, give this term for a molecule or ion that binds to a central atom in a coordination complex. ■END■