Synthesis and characterization of the novel shape-persistent nanosized cavity macrocycle

The Friedel–Crafts reaction was employed to prepare the shape-persistent macrocycle (TPAP)3 with direct cyclization from three monomers of 2-(4′-(Phenyl(4″-methylphenyl)amino) phenyl)-propan-2-ol (TPAP), which contains two reactive groups of the t-hydroxyl and the p-proton on the triphenylamine. Under a very low monomer concentration (ca. 1%), the yield of the shape-persistent macrocycle (TPAP)3 is up to 34%. FT-IR, NMR, MALDI-TOF and MS were applied to determine the structure of macrocycle. It can be a good candidate as the hole-transporting layer because its photoluminescent spectrum appears no emission peaks in the range of 400–600 nm. The geometry of (TPAP)3, optimized by the density functional theory (DFT) calculations using Gaussian03 software at the B3LYP/6-31G(d) level, showed that (TPAP)3 possesses an approximately 10 Å diameter and 8.4 Å depth molecular inner cavity. Owing to three nitrogenous lone electron pairs and six conjugated large π bonds of the macrocyclic electron-excessive phenylene almost directing into the cavity, the macrocycle is a big electron-rich donor which may be favorable for selective extraction of special diameter metal ions, high effective and selective catalysis and the formation of 1:1 π-donor–π-acceptor (C60) complexes through the host–guest interactions.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Friedel–Crafts reaction was employed to prepare the new shape-persistent macrocycle (TPAP)3. ► The yield of (TPAP)3 is up to 34%. ► (TPAP)3 possesses about Φ10 × 8.4 Å molecular inner cavity. ► The macrocycle is a big electron-rich donor. ► It could form 1:1 π-donor–π-acceptor (D–A) complexes with C60.