Synthesis of complanadine A and phthaloyl peroxide-mediated oxidations of alkenes and arenes
The natural product complanadine A has shown promise in regenerative science, promoting neuronal outgrowth by inducing the secretion of growth factors from glial cells. Through the use of tandem, cobalt-mediated [2+2+2] cycloaddition reactions two synthetic routes have been developed with different sequences for the formation of the unsymmetric bipyridyl core. The regioselective formation of each of the pyridines was achieved based on the inherent selectivity of the molecules or by reversing this inate regioselectivity through the addition of Lewis bases. This strategy has been successfully employed to provide laboratory access to complanadine A as well as structurally related compounds possessing the lycodine core. Phthaloyl peroxide derivatives have the potential to function as organocatalysts for the dihydroxylation of alkenes. The development of an organocatalytic system for the syn-dihydroxylation of alkenes, using hydrogen peroxide as the stoichiometric oxidant, could minimize the waste and cost associated with the current industrial process. With new access to phthaloyl peroxide derivatives, this dihydroxylation method was improved with stoichiometric dichlorophthaloyl peroxide for the dihydroxylation of alkenes. Substituted phenols are broadly useful compounds, functioning as starting materials and end products in all areas of chemical industry. Since the initial discovery of phenol from coal tar advances have been made in the synthetic preparations of this class of compounds which possess a hydroxyl group appended to an aromatic hydrocarbon core. Ideally the synthesis of phenols is achieved through the direct installation of oxygen into an aromatic precursor, which is typically more abundant. In this thesis it is discussed how phthaloyl peroxide, in the absence of other reagents, enables the conversion of aromatic hydrocarbons to phenols even when the precursors possess functionality that is incompatible with strongly oxidizing conditions. The reaction is shown to proceed through a "reverse rebound" mechanism as opposed to the classical rebound mechanism, providing insight into the unique aryl selectivity of the chemical transformation.