Synthesis and Dimerization of Chloro10cycloparaphenylene: A Directly Connected Cycloparaphenylene Dimer

The first synthesis and dimerization of monochlorinated 10cycloparaphenylene (chloro10CPP) are described. By assembling a chlorinated 1,4-diborylbenzene unit with brominated and borylated cis-1,4-diphenylcyclohexane units by Suzuki-Miyaura coupling, a triangle-shaped chloro-containing macrocycle was synthesized. The acid-mediated "cyclohexane-to-benzene" aromatization afforded chloro10CPP without losing the chloro group. By the action of Ni(0) complex, chloro10CPP was converted to a directly connected 10CPP dimer, which would be an ideal precursor for the "carbon nanobelt".