Construction of Supramolecular Nanostructures from V-Shaped Amphiphilic Rod-Coil Molecules Incorporating Phenazine Units

Abstract

Abstract:A series of bent-shaped molecules, consisting of dibenzo [a,c]phenazine and phenyl groups connected together as a rod segment, and poly(ethylene oxide) (PEO) with a degree of polymerization (DP) of 6 as the coil segment, were synthesized. The self-assembling behavior of these molecules by differential scanning calorimetry (DSC), thermal optical polarized microscopy (POM), small-angle X-ray scattering spectroscopy (SAXS), atomic force microscopy (AFM), and transmission electron microscopy (TEM), revealed that carboxyl or butoxy carbonyl groups at the 11 position of dibenzo[a,c]phenazine noticeably influence self-organization of molecules into supramolecular aggregates in bulk and aqueous solutions. Molecules 1 and 2 with chiral or non-chiral PEO coil chains and the carboxyl group at the rod segments self-organize into a hexagonal perforated lamellar structure and a hexagonal columnar structure in the solid state. In aqueous solution, molecules 1 and 2 self-assemble into diverse lengths of nanofibers, whereas molecules 3 and 4 with butoxy carbonyl groups exhibit a self-organizing capacity to form diverse sizes of spherical aggregates.

Comparative Study of Conventional/Ethoxylated/Extended n-Alkylsulfate Surfactants

“…It is evident that there is a positive correlation between S and p , which indicates that the PPO spacer at the air/water surface might “extend” along the surface more than just extends molecular length, and the longer the PPO spacer, the more obvious the rugby shape of e-surfactant is. Previous reports have found that PPO chain embedded in surfactant or polymer molecules is generally described as a PPO coil , similar to a PEO coil. , Thus, a longer PPO spacer of e-surfactants on the monolayer adsorption would coil more and collapse more by surface-induced interaction to result in a larger S . Additionally, molecular surface area values of the e-surfactants (C 14 –C 18 ) with a same length of PPO chain are slightly greater than the corresponding n -C 12 P p S series.…”

“…Previous reports have found that PPO chain embedded in surfactant or polymer molecules is generally described as a PPO coil 59,60 similar to a PEO coil. 61,62 Thus, a longer PPO spacer of e-surfactants on the monolayer adsorption would coil more and collapse more by surfaceinduced interaction to result in a larger S. Additionally, molecular surface area values of the e-surfactants (C 14 −C 18 ) with a same length of PPO chain are slightly greater than the corresponding n-C 12 P p S series. In a word, the intramolecular PPO spacer of e-surfactants should coil to extend surface area more than stretch to extend molecular length, making esurfactant molecules being in rugby shape at the air/water surface, and it is rational to be extended to other interfaces according to our previous research 3 and even in bulk phases.…”

Acetatos trinucleares de rutênio coordenados a ligantes fenazínicos: estudos sobre síntese, reatividade, interações com DNA e avaliação do potencial tripanocida

“…Moléculas como as fenazinas e derivados, que são planares, rígidas, πconjugadas e aromáticas, podem formar agregados moleculares em solução. Estes agregados são mantidos por forças intermoleculares fracas, resultando em equilíbrios de formação de dímeros, trímeros ou agregados de maior ordem, processo conhecido como empilhamento π (do inglês π-stacking) (BRAGA et al, 2014;CHEN et al, 2009b;XU et al, 2017). A característica responsável pela natureza das forças intermoleculares nestes agregados é a presença de nuvens π, onde a densidade eletrônica nos anéis aromáticos de uma molécula pode interagir com os elétrons nos anéis de outra (chamado interação π-π).…”