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The mass spectra of endo,endo-1,2,3,4,4a,5,8,8a-octahydro-1,4:5,8-dimethanonaphthalen-anti-2-01 (Ia) and its endo,exo-2-ol (IIa) and endo,exo-10-ol (IIIa) isomers have been examined. Fragmentation schemes have been constructed on the basis of metastable transition measurements, accurate mass determination and deuterium substitution. A presence of the double bond in the molecule and a favourable hydrogen atom orientation in the vicinity of the double bond play an important role in the ion degradation process.

Specifically deuterated brosylates of unsaturated carbinols with endo-, exo-fused norbornanes structure 4-0H were prepared and their acetolysis rates measured at 25.0 °c. A secondary a-deuterium isotope effect of kH/kn = 1.20 was obtained which is close to the characteristic maximum for solvolysis of sulfonate esters. This result is rationalized in terms of an exponential correlation between the magnitude of the a-d effect and the bond order to incoming and leaving groups. The conclusion is reached that even large rate accelerations may indicate extensive charge delocalization occurring at large internuclear distances between the neighboring group and the reaction center in the transition state. Acetolysis of the compound with deuterated double bond (4-0Bs-d6) proceeds with an inverse isotope effect (kH/kn = 0.93) which is analogous to other cases of n-participation.