Carbon-13 nuclear magnetic resonance spectra of 3,7-disubstituted bicyclo[3.3.1]nonanes: conformation and through-space interaction

Abstract

Carbon-13 n.m.r. spectra of several bicyclo[3.3.1]nonane derivatives were measured. The conformation of the framework of bicyclo[3.3.1]nonanes in this study was confirmed by the carbon chemical shifts. The π-electron delocalization was recognized in 3,7-dimethylenebicyclo[3.3.1]nonane and 7-methylenebicyclo[3.3.1]nonan-3-one due to the intramolecular through-space interaction between two π-orbitals.