Reaction of (Z)-[6]paracycloph-3-ene (1) with tetracyanoethylene gave [2+2] cycloadduct 4 and that with trifluoroacetic acid in methanol afforded 1,4-adduct 8.
Metalation of [6]paracyclophane (1) with a superbase generated metalocyclophanes 2a and 3a regioselectively which led to mono substituted derivatives 2b–2e and para disubstituted 3b, 3d, and 3e.
[6]paracyclophane (1) has been synthesized by oxidative decarboxylation of [6.2.2]propellenecarboxylic acid with leadtetraacetate. Vapor phase thermolysis of 1 affords 3-methylene-spiro[5.5]undeca-1,4-diene predominantly, while acid-catalyzed rearrangement of 1 gives the meta and ortho isomers in a ratio of 1:3.
The unusual reactivity of [6](1,4)naphthalenophane (2) and [6](1,4)anthracenophane (3), the smallest-bridged acenophanes hitherto known, in electrophilic reactions has been disclosed. These reactions include (i) acid-catalyzed telomerization, (ii) peracid oxidation, and (iii) addition with dienophiles. Semi-empirical molecular orbital calculations (MNDO and MNDO/PM3) were performed in order to compare