LAUSR

Abstract A variety of functionalized cage compounds and D3-trishomocubane derivatives have been assembled via the Diels–Alder strategy, with reductive cleavage of the cyclopropane ring and metal promoted ring rearrangement as key steps. We have installed the gem-dimethyl moiety on the norbornane ring system containing a cage framework by a late-stage synthetic manipulation involving the hydrogenolysis of the cyclopropane ring with the aid of Adams’ catalyst (PtO2). Several cage molecules containing methyl substituents were synthesized by starting with inexpensive and commercially available materials such as 2,3-dimethylhydroquinone, Zn/AcOH, and endo-dicyclopentadiene. These cage pentacycloundecane frameworks assembled here are difficult to synthesize by conventional routes. Some of these gem-dimethyl cage systems and D3-trishomocubane derivative was firmly supported on the basis of single-crystal X-ray diffraction studies.