rearrangement of tricyclo[5.4.0.01,5]undecan-ll-one gave tricyclo[5.3.1.01,5]undecan-11-one in a nonnucleophilic media and tricyclo[5.4.0.03,8]undecane-7, 8-diol in the presence of a nucleophile, respectively. Tricyclo[5.4.0.01,5]undecan-11-ols also rearranged to tricyclo[5.4.0.03,8]undecan-7-ol. A reductive rearrangement with a hydride transfer of the alcohol gave only tricyclo[5.4.0.03,8]undecane.