Self-Assembly of Aromatic-Derivatized Amphiphiles:  Phenyl, Biphenyl, and Terphenyl Fatty Acids and Phospholipids

Abstract

This paper reports the synthesis of a series of amphiphiles (fatty acids and phosphatidylcholine derivatives) containing phenyl, biphenyl, and terphenyl chromophores inserted in the hydrocarbon chain and a study of their self-assembly in Langmuir−Blodgett films and aqueous dispersions. As observed and reported earlier for amphiphiles containing trans-stilbene, styrylthiophene, or azobenzene chromophores, several of the biphenyl and terphenyl derivatives show strong evidence of ground state association to form “H” aggregates characterized by a blue shift in absorption and a structured, red-shifted fluorescence. The phenyl amphiphiles show different behavior, suggesting that, even for pure films or bilayers, there is very little or no ground state association. For the biphenyl and terphenyl phospholipids, aqueous suspensions obtained by sonication are closed bilayer vesicles similar in size to those formed from the corresponding saturated phospholipids. The overall results of the present study indicate that biphenyl and terphenyl amphiphiles undergo aggregation processes to form compact arrays formally similar to those observed with stilbene, tolan, azobenzene, and squaraine derivatives but that the aromatic−aromatic interactions are considerably weaker than those for the more extended aromatics and lead to less distortion of the assembly structure.

Hole‐buffer polymer composed of alternating p‐terphenyl and tetraethylene glycol ether moieties: Synthesis and application in polymer light‐emitting diodes

“…The PL bathochromic shift can be explained by the formation of p ‐terphenyl aggregates in film state, which brings about reduced LUMO level in excited state. To conclude, in film state, the 3P5O shows strong evidence of ground state association to form “H” aggregates characterized by a blue shift in absorption and a structured, red‐shifted fluorescence …”

“…The absorption maximum in film state shifts hypsochromically (9 nm) relative to that in CHCl 3 solution. This is caused by ground state association of the p ‐terphenyl groups to form “H” aggregates in film state, which is characterized by a blue shift in absorption . On the contrary, the PL spectral maximum is significantly red‐shifted from 355 to 393 nm in going from solution to film state.…”

“…This is caused by ground state association of the p-terphenyl groups to form "H" aggregates in film state, which is characterized by a blue shift in absorption. 27,28 On the contrary, the PL spectral maximum is significantly red-shifted from 355 to 393 nm in going from solution to film state. The PL bathochromic shift can be explained by the formation of p-terphenyl aggregates in film state, which brings about reduced LUMO level in excited state.…”

Solvent-tuned multiple self-assembly of a new sugar-appended gelator

“…THF is a good solvent of 1. In THF, 1 exhibited a wellresolved absorption peak centered at 266 nm, which was assigned to the 1 B 2u ← 1 A g transition of biphenyl [38,39]. Heating the solution to 65 • C resulted in no appreciable change in the spectrum.…”

Optically Active Oligomer Units in Aggregates of a Highly Unsaturated, Optically Inactive Carotenoid Phospholipid

“…In various attempts to introduce chromophores, phospholipids with stilbene, biphenyl, terphenyl, and azobenzene fatty acids have been synthesized. [9][10][11] Likewise, a glycerophosphatidylcholine enantiomer with styrylthiophene acyl groups was synthesized, which was devoid of optical activity. [12] Undoubtedly, the mentioned lipids contain rather xenobiotic acyl groups and are, therefore, different from lipids of naturally occurring fatty acids.…”