The high acidity of cubylamine (1NH(2)) seems to originate in the release of strain energy attending the breaking of some C-C bonds in 1NH(-). This process is greatly facilitated by the strong stereoelectronic interactions in 1NH-. The anionic species thus formed are less strained, and their corresponding conjugate acids seem unable to 'borrow strength' from the residual strain, at least within the time-scale of the FT ICR experiments. (C) 2004 Elsevier B.V. All rights reserved.