%0 Generic
%9 Doctoral Dissertation
%A Park, Jung-hyun
%D 2011
%F pittir:9715
%K Diels-Alder; imine; ketene
%T STUDIES ON AZA-CYCLOADDITION:PART 1. INTRAMOLECULAR KETENE-IMINE CYCLOADDITIONPART 2. IMINIUM ION-MEDIATED [4+2] CYCLOADDITION
%U http://d-scholarship-dev.library.pitt.edu/9715/
%X Part 1. Intramolecular Ketene-Imine CycloadditionThe ketene-imine cycloaddition reactions, developed previously by the Nelson group, have beenextended to the intramolecular cycloaddition of the ketene-imine cycloaddition. Initial resultsshowed that the intramolecular cycloaddition exhibited excellent enantioselectivity, but it wassuffered from poor diastereoselectivity. Later, it was shown that proper functionality on thetether of the substrate could improve diastereoselectivity.Part 2. Iminium Ion-Mediated [4+2] CycloadditionThe N-alkenyl iminium ion cycloaddition reaction (AIC reaction), developed previously by theNelson group, was further investigated for the more detailed understaniding. As a result, tworeaction pathways (Diels-Alder pathway and oxo-Diels-Alder pathway) of the AIC reaction werefound when carbamate-protected N-alkenyl iminium ion was employed as a 4Ĉ-electroncomponent. Based on this observation, efficient methods to turn off either one of the tworeaction pathways were proposed.