Hyperconjugation/conjugation through-bond stereoelectronic effects were studied with density functional theory (DFT) in the context of 3-azabicyclo[3.3.1]nonanes to unravel puzzling differences in reactivity between a vinylogous chloride (4) and a vinylogous ester (5). These compounds—whose structures differ only by one substituent—were found to display strikingly different reactivities in hydrochloric acid by Risch and co-workers (J. Am. Chem. Soc. 1991, 113, 9411–9412). Computational analyses of substituent effects, noncovalent interactions, natural bond orbitals, isodesmic reactions, and hydration propensities lead to a model for which the role of remote, through-bond stereoelectronic effects is key to explaining 4 and 5’s diverging reactivity.
Hyperconjugation/conjugation
through-bond stereoelectronic effects
were studied with density functional theory in the context of 3-azabicyclo[3.3.1]nonanes
to unravel puzzling differences in reactivity between a vinylogous
chloride (4) and a vinylogous ester (5).
These compoundswhose structures differ only by one substituentwere
found to display strikingly different reactivities in hydrochloric
acid by Risch and co-workers (J. Am. Chem. Soc.199111394119412). Computational
analyses of substituent effects, noncovalent interactions, natural
bond orbitals, isodesmic reactions, and hydration propensities lead
to a model for which the role of remote, through-bond stereoelectronic
effects is the key to explaining 4 and 5’s diverging reactivity.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.