Enantioselective synthesis of π-extended carbo[17]helicene via sequence-controlled quadruple [2+2+2] cycloadditions

Sequence-controlled quadruple [2+2+2] cycloadditions, followed by onward Scholl reactions, enable the enantioselective synthesis of a giant π-extended carbo[17]helicene from a dodecayne substrate. This Ni-catalysed process forms a chiral nanocarbon that exhibits strong circularly polarized luminescence.