IONIC REACTIONS IN BICYCLIC SYSTEMS .8. ACETOLYSIS OF SYN- AND ANTI-7-CHLORO-EXO-NORBORNYL P-TOLUENESULFONATES

Acetolysis of syn- (I-OTs) and anti-7-chloro-exo-norbornyl p-toluenesulfonate (II-OTs) has been reinvestigated. Ion-pair return associated with solvolysis results in isomerization of I-OTs to II-OTs; at 70% solvolysis of I-OTs the composition of the unsolvolyzed ester is about 70% I-OTs and 30% II-OTs. Isomerization in the opposite direction is unimportant. The I-OTs→ II-OTs isomerization involves a 6,2-hydride shift and migration of the anion from C2 to C6. This transformation is intramolecular (very little exchange with p-toluene-sulfonate ion) and evidently involves internal return. Intermediates generated from I-OTs and II-OTs undergo 6,2-hydride shifts in competition with solvent capture. © 1969, American Chemical Society. All rights reserved.