Fullerene‐ and porphyrin‐appended crown ethers: Synthesis and preparation of stable langmuir and langmuir‐blodgett films

Abstract

The synthesis of a series (1–5) of fullerene and Zn(II)‐porphyrin amphiphiles with polar dibenzo[24]crown‐8 headgroups is described. Their ability to form Langmuir monolayers at the air‐water interface was investigated in a systematic study. The Langmuir films were characterized by their surface pressure versus molecular area isotherms, compression and expansion cycles, and Brewsterangle microscopy. Complexation of larger alkali metal cations (K+ and Cs+) by the polar headgroups leads to higher molecular area requirements and a better anchoring to the aqueous subphase. The monolayers of the porphyrin‐(dibenzo[24]crown‐8) conjugates were transferred as Langmuir—Blodgett films onto glass slides and the films characterized by UV‐vis spectroscopy and grazing‐incidence X‐ray diffraction. Good evidence was obtained that the porphyrin‐fullerene‐crown ether triad 5 adopts a sandwich geometry in the LB films. In such an arrangement, the electron‐attracting carbon sphere benefits from attractive interactions with the sandwiching electron‐rich porphyrin and crown ether chromophores. The described films could have potential applications as functional materials in optical and electronic technology.

[60]Fullerene–porphyrin [n]pseudorotaxanes: self-assembly, photophysics and third-order NLO response

“…22,23 Similar results have been also reported with other covalent fullerene-containing dyads, [35][36][37][38][39][40] however, to the best of our knowledge, the effect of non-covalent [41][42][43][44][45][46] linkages on the third-order NLO responses is yet unknown for such fullerenebased systems. Diverse crown ethers have been employed in C 60 recognition processes [47][48][49][50][51][52][53][54][55][56][57][58][59][60][61] and the construction of [n]pseudorotaxane motifs is certainly one of the most versatile approaches to assemble molecular chromophores. Therefore, the formation of a supramolecular complex between dibenyl ammonium (DBA) cation and a dibenzo-24-crown-8 (DB24C8) ether macrocycle is one of the leading methods which could be exploited to prepare a porphyrin- [60]fullerene [2]pseudorotaxanes.…”

Tying a knot between crown ethers and porphyrins

“…Osuka and co-workers provided novel insight into the meso -appended crown ether porphyrins, namely, chromophore-incorporated and polymer-based systems capable of acting as multitopic receptors for transition, alkali, and alkali-earth metal cations, which were proved as optical sensing agents among other applications [ 43 – 44 78 ]. Fullerene-based crown ether-appended porphyrins developed by Diederich and co-workers were used as polymeric material films [ 79 ]. Intriguing supramolecular systems capable of electron transfer were developed by D'Souza, Ito and co-workers, showing selective multitopic receptors binding different alkali and transition metal cations with intramolecular photoinduced electron transfer [ 48 , 80 ].…”

Synthesis and characterization of a new porphyrin–polyoxometalate hybrid material and investigation of its catalytic activity

“…21 There are numerous supramolecular constructs of porphyrins and electron-acceptor species such as C 60 . [22][23][24][25][26][27] In addition to POMs being good electron acceptors, in many ways the diverse photochemical, and coordination chemistry of porphyrins and POMs are complementary. Therefore, robust complexes incorporated by porphyrins and POMs should have expected unique properties.…”