Several N-substituted nortropane and norgranatane derivatives were synthesised from tropinone and granatanone. The equilibrium distributions of the axial and equatorial N-invertomers of the free amine forms of the prepared products in methanol and their protonated forms (hydrochlorides) in water were studied by low-temperature and room-temperature NMR spectroscopy. Theoretical distributions in the gas phase, methanol and water solvents were calculated using DFT methods and compared with inverse gated ¹³C NMR experiments. DFT calculations provided results in reasonable agreement with experimental data. Equatorial invertomers dominated in N-tert-butyl- and N-benzylnortropinone, and the equatorial/axial ratio for N-ethyl- and N-phenethylnortropinone was close to 1. The axial invertomers dominated in all of the granatanone derivatives and the N-isopropyl- and N-phenylnortropane. Our experiments indicated that nitrogen protonation shifted the invertomer equilibrium towards equatorial forms. DFT calculations reproduced this effect for tropanes.