Dodecahedrane fully unsaturated

Triquinacene 10 which is now reasonably well accessible by a six to seven step synthesis [1,2], has long been envisaged as the logical precursor to acepentalene 3 [43] (see Scheme lb). Woodward et al. developed the first synthesis for triquinacene 10 [43] and suggested that it should be a potential precursor to both the fully unsaturated tricycle acepentalene 3 and dodecahedrane 88 [ 1,44]. Although many attempts have been made to cyclodimerize triquinacene 10,... 

Therefore stepwise introduction of double bonds into the saturated dodecahedrane 88 is the only logical alternative approach towards the fully unsaturated C20-fullerene 7. Paquette et al. have reported a /1-elimination of trifluoroacetic acid from (trifhioroacetoxy)dodecahedrane 135 with hydroxide and methoxide ion in an ion cyclotron resonance mass spectrometer to infer indirectly the... 

Also the fully unsaturated C20-fullerene 7 has been approached by Prinzbach et al. [44, 97]. As suitable precursors the perchlorinated dodecahedradiene C20C116 145 and the perbrominated dodecahedrane C20Br20 146 were prepared from 88 under forcing conditions. Due to their low solubility these compounds have so far only been identified by their infrared and mass spectra. Dehaloge-nation by fragmentation in the mass spectrometer has generated several unsaturated species but the occurrence of C20-fullerene 7 remains to be rigorously proved. 

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