ABSTRACT
Interest in alicyclic highly strained cage molecules has accelerated greatly during the past decade, and these compounds continue to fascinate chemists since their synthesis is a major challenge. These molecules also have useful physical and chemical properties and biological activity. The extensive efforts devoted to the synthesis of these molecules are described in this chapter. One of the most important components of the cage compounds is a highly strained cyclobutane ring (strain energy 26.4 kcal/mol). The first synthetic approach to a cyclobutane ring via a photochemical reaction was reported by Ciamician and Silber in 1908.
