Exploiting the Reactivity of Dienes via Electrophilic Addition with Anionic and Radical Intermediates

Our group’s main focus has been to answer the question of direct functionalization at the γ-position of cycloalkanones. To this day, countless chemical transformations are known for the functionalization of the α- and β-positions of cyclic ketones. However, few methods are known for functionalization at the γ-position of cycloalkanes. Our group has set out to resolve this problem by examining stabilized dienolate intermediates in both anionic and radical conditions. These reactive intermediates have opened a wide array of product possibilities upon exposure to a series of diverse reaction partners. Through these methods, our group has managed to find conditions in which formation of new carbon–halogen bonds, carbon–oxygen and carbon–carbon bonds occurs selectively at the γ-position of enones and related systems. Additionally, the reactivity of dienes in pyrrole systems has also been studied. As a result, a protocol to access new sterically demanding halopyridines via the Ciamician–Dennstedt rearrangement has been discovered. Furthermore, an economical and efficient synthesis of 2,6-di-t-butylpyridine analogues, along with gas-phase proton affinity studies of these compounds, has also accomplished.