PUB - Publikationen an der Universität Bielefeld

Tribenzodihydroacepentalenediide 5, a potential precursor for tribenzoacepentalene 6, can be prepared in good yields from the easily accessible centro-substituted tribenzotriquinacenes 7a-c by treatment with an excess of n-butyl lithium/potassium t-pentoxide in the presence of tetramethylethylene diamine (TMEDA). The dimer 16 of tribenzodihydroacepentalene 15, thus obtained after hydrolysis of 5 in up to 85% yield from readily accessible 7a, undergoes [2+2]-cyclo-reversion at 220-degrees-C, and 15 is efficiently trapped in [2+4]-cycloadditions with non-volatile dienes like tetracyclone and anthracene to give structurally interesting polycycles 17 and 18, respectively.