Synthesis and properties of trefoil-shaped tris(hexadehydrotribenzo[12]annulene) and tris(tetradehydrotribenzo[12]annulene).

[reaction: see text] Trefoil-shaped tris(hexadehydrotribenzo[12]annulene) possessing a substructure of the ultimate two-dimensional C(sp)-C(sp(2)) network, graphyne, and the related tris(tetradehydrotribenzo[12]annulene) were synthesized, and their ground- and excited-state properties were investigated.