About the Seminar: 

Alkenes are ubiquitous building blocks in synthetic chemistry that are leveraged in difunctionalization strategies to append multiple groups in one step. However, methods to achieve this typically require specialized reagents, directing groups, and/or transition-metal catalysts for reactivity and reliable selectivity. Recent work has shown 1,3-alkene difunctionalization via charge relocation. Key to this method is the use of acylium salts that form cyclic intermediates with alkenes in a stepwise fashion that can be quenched with a nucleophile. Nitrilium salts represent an interesting analogue to acylium salts, often engaged as intermediates in a number of transformations such as the Schmidt, Ugi, and Ritter reactions. However, nitrilium salts have not been reported in alkene difunctionalization reactions. Nitrilium ions would be ideal for alkene difunctionalization as they possess two modular R-groups and the resulting imines can be further functionalized into ketone and amine products. Additionally, nitrilium ions are benchtop stable and easily accessible via nitrile alkylation/arylation or elimination from imidoyl chlorides. Similarly, nitronium ions can serve as alternate reaction partners in a nitration-functionalization process. Overall, this proposal aims to develop effective 1,2- and 1,3- difunctionalizations of alkenes using nitrilium and nitronium salts.