Development of methodologies aiming to the synthesis of 2-(trimethylsilyl)aryl triflates as precursors of arynes with application in reactions of insertion into sigma bonds, in reactions of cycloaddition and in the production of aporphine alkaloids

Abstract

Owing to the considerable importance of 2-(trimethylsilyl)aryl triflates in the current context of the benzyne chemistry, we intend to prepare 2-(trimethylsilyl)aryl triflates with novel structures, envisioning the employment of such aryne precursors in intramolecular reactions of insertion into heteroatom-hydrogen sigma bonds, in order to produce different classes of compounds, namely: carbazoles; dibenzofurans; depsidones and depsazidones, which constitute the basic structures of a number of substances with pronounced biological activities. In parallel, we wish to explore the hetero-Diels-Alder reaction between alpha,beta-unsaturated carbonyl compounds and known 2-(trimethylsilyl)aryl triflates using mild reaction conditions, in the formation of functionalized benzopyrans, which are present in the structures of various natural products, bioactive substances and functional materials. Simultaneously, we intend to develop the convergent total syntheses of the aporphine alkaloids lisicamine, PO-3 dye, (R)-(-)-aporphine and (R)-(-)-apormorphine, employing strategy which involves key reaction of [4+2] cycloaddition between 1-methylene-1,2,3,4-tetrahydroisoquinolines and arynes, formed from their corresponding 2-(trimethylsilyl)aryl triflates, under mild reaction conditions. (AU)