Intramolecular [4 + 2] cycloadditions of conjugated enynes with highly strained cyclic alkenes

Abstract

Seven- and eight-membered carbocycles are key features in numerous naturally occurring organic substances, many of which are biologically important natural products. This thesis describes studies directed towards the development of a [4 + 3] annulation strategy for the synthesis of seven-membered carbocycles involving the intramolecular [4 + 2] cycloadditions of conjugated enynes with cyclopropenes. A new [4 + 4] annulation method has been developed for the synthesis of eight-membered carbocycles involving cycloadditions of cyclobutenones with conjugated enynes.