A negatively curved carbonyl-bridged triphenylamine

Abstract

Planar and positively curved carbonyl-bridged triphenylamine derivatives with five- and six-membered rings around the central nitrogen atom have been extensively studied. However, the incorporation of seven-membered rings to form negatively curved carbonyl-bridged triphenylamine derivatives is still scarce. Herein, we report the synthesis of a negatively curved carbonyl-bridged triphenylamine compound bearing double hexagonal rings and a heptagonal ring around the central nitrogen atom. The peripheral double bond of the heptagonal ring can be oxidized to form an adjacent diketone compound with room temperature phosphorescence. Naphthalene and quinoxaline units can be fused to the seven-membered ring to give saddle-shaped derivatives, which can assemble with C₆₀ in a 1 : 1 ratio in toluene, with different binding constants depending on the fused units.