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The ¹H and ¹³C NMR chemical shift assignments of 10-substituted decal-2-ones, cis (H, CH3 and CO2CH3) and trans (H, CH3, OH and CO2C2H5) were based on 2D COSY and HETCOR experiments, supported by selective spin decoupling experiments. The discrimination between the cis and the trans conformations was ruled out on the basis of the J(1a,9) magnitudes related to dihedral angles (Karplus rule) and also on the ¹³C shielding values of C-4 of the cis compounds, which are much more shielded than those of the trans counterparts. The best and fastest criterion of differentiation between cis and trans conformers is the constant appearance in the ¹³C PND spectra of the cis series of some signals of broadened linewidth and low intensity, essentially C-4, C-5 and C-7, a clue to site exchange processes; the trans counterparts showed only sharp signals because of their existence as a single conformation. Copyright © 2000 John Wiley & Sons, Ltd.

A series of 6-exo-acetoxybicyclo[2.2.2]octan-2-ones were converted into the corresponding 6-exo-hydroxybicyclo[2.2.2]octan-2-ones by methanolysis in the presence of CH3ONa/La(OTf)3. Under the given conditions, epimerization at C(6) of the latter led in the least favorable cases only to traces of the more stable 6-endo-hydroxybicyclo[2.2.2]octan-2-ones. This procedure, when combined with the described conversion of easily available 6-endo-hydroxybicyclo[2.2.2]octan-2-ones into the corresponding 6-exo-acetoxy derivatives, provides a convenient route to elusive 6-exo-hydroxybicyclo[2.2.2]octan-2-ones. Applications to total synthesis are shown and envisaged.