Two Model Compounds to Investigate the Gear Effect: 2,3-Dialkyl-Bicyclo[2.2.1]-Heptane and 2,3-Dialkyl-Bicyclo[2.2.2]-Octane

Compounds I, II and III, were used as models resembling gear systems (bods connecting CR3 groups to the skeletal molecule are parallel) in surveying the potential energy surface for their internal rotation. The magnitude of the barriers calculated for averaging the NMR signals, placed these compounds in the range of measurement accessible by dynamic NMR spectroscopy (which is currently being pursued).