Abstract
Construction of a methylenecyclopentane ring is an important issue in synthesis of natural products. This thesis delineated a newly developed process toward highly functionalized methylenecyclopentanes. Recently, we developed an efficient methylenecyclopentane annulation process to construct the functionalized methylenecyclopentanes. The efficient methylenecyclopentane annulation involves a convenient 1,4-addition of (4-buty-1-nyl)trimethylsilane magnesium chloride to 2-cyano-2-cycloalkenone 1 and following a zinc iodide promoted annulation of the resulting bicyclic product 3. We also developed the process toward methylenecyclohexane annulation via compound 4 under the same condition. This annulation process can be accomplished in mild condition and the yield is high. The utility of the functionalized methylenecyclopentane annulation was also be studied.