4. NORBORNANES. PART 19. THE INDUCTIVE MODEL FOR NORBORNYL CATION FORMATION

Article abstract of DOI:10.1002/hlca.19870700105

Two CH3 groups at C(6) of 2-exo- (10a) and 2-endo-norbornyl p-toluenesulfonate 11a lower their solvolysis rates in 80 percent EtOH by factors of 28 and 16, respectively.A spirocyclopropyl group including C(6), as in 21a and 22a, reduces the rate of exo- and endo-ionization by factors of 250 and 8, respectively.The geminally dimethyl-substituted tosylates 10a and 11a yield the 2-exo-alcohol 10b, whereas the spirocycclopropyl-substituted tosylates 21a and 22a furnish rearranged 3-brendanol 23.These findings are readily rationalized by the inductive model, according to which norbornyl cation formation is controlled by the inductive effect of dorsal substituents.