prepared as precursors of three-dimensionalpolyynes C78H18 (1a) and C78H12Cl6 (1b), respectively. Laser irradiation of 2a and 2b induced expulsion of the aromatic fragment, indane, to give the three-dimensionalpolyyne anions C78H18- and C78H12Cl6-, respectively. Whereas the former anion lost only four hydrogen atoms to form C78H14-, complete loss of all hydrogen and chlorine atoms was observed from the latter
[6(n)]Paracyclophenediynes 2a-d (n = 3-6) having [4.3.2]-propellatriene units were prepared as precursors of the corresponding [6n]paracyclophynes. Laser irradiation of 2a-d produced the negative ions of [6n]paracyclophynes 1a-d (n = 3-6) by extrusion of the indan fragments, which were detected by time-of-flight mass spectrometry.
[16.16.16](1,3,5)Cyclophanetetracosayne (C<sub>60</sub>H<sub>6</sub>): A Precursor to C<sub>60</sub> Fullerene