Quantum chemical study of tautomerism of bullvalene, bullvalenol, and the corresponding ketone

Using the quantum chemical method PBE0/cc-pVTZ, we determined structural parameters and dipole moments of bullvalene (tricyclo3.3.2.0^4.6]deca-2,7,9-triene), 1-, 2-, 3-, and 4-hydroxytricyclo3.3.2.0^4.6]-deca-2,7,9-trienes, and isomeric 2- and 3-ketones transforming into each other through the keto-enol tautomerism and Cope rearrangement with the triatomic ring migration. The dominant tautomer is 3-ketone containing a triatomic ring conjugated with the carbonyl group.