Deamination of 2-amino-4, 4-dideuterio-6, 6-dimethylcyclohexanone, 2-exo-amino-and 2- endo-amino-norbornane-3-one, 2-diazo-norbornan-3-one, 2-exo-amino-5, 6-exo- dideuterionorbornan-3-one and the corresponding 5, 6-endo-dideuterio isomer has been studied. The nature of the products, the deuterium location in them, and the high retention of steric identity in the carbocations are interpreted in terms of σ-bond participation leading to ...