Synthesis of tripyreno[2,3,4-abc : 2,3,4-ghi : 2,3,4-mno][18]annulenes

The title compounds were prepared in a multi-step synthesis in which primar ily the pyrene building blocks were formed (1.2 --> 11a.b). The final react ion step 11a,b --> 12a,b consisted of a threefold trans selective cyclocond ensation process that generated the central 18-membered ring. Hexyl oxy or dodecyloxy sidechains attached on the periphery led to the formation of liq uid crystalline phases.