Self‐Assembly of Semifluorinated Dendrons Attached to Electron‐Donor Groups Mediates Their π‐Stacking via a Helical Pyramidal Column

Abstract

Semifluorinated first-generation self-assembling dendrons attached via a flexible spacer to electron-donor molecules induce pi-stacking of the donors in the center of a supramolecular helical pyramidal column. These helical pyramidal columns self-organize in various columnar liquid crystal phases that mediate self-processing of large single crystal liquid crystal domains of columns and self-repair their intracolumnar structural defects. In addition, all supramolecular columns exhibit a columnar phase at lower temperatures that maintains the helical pyramidal columnar supramolecular structure and displays higher intracolumnar order than that in the liquid crystals phases. The results described here demonstrate the universality of this concept, the power of the fluorous phase or the fluorophobic effect in self-assembly and the unexpected generality of pyramidal liquid crystals.

Perfluorocarbons: Life sciences and biomedical uses Dedicated to the memory of Professor Guy Ourisson, a true RENAISSANCE man.

“…30,31 Highly organized helical pyramidal columns were formed by self-assembly of semifluorinated dendrons attached to electron-donor groups. 32 These columns subsequently self-organize into large supramolecular pyramidal liquid crystals. Further examples of controllable spherical or tubular micro-and nanosized fluorinated environments are found in self-assembled vesicles, tubules, ribbons, as well as in a variety of microbubbles and microdroplets, as in aerosols, emulsions, microemulsions, reverse emulsions, gel-emulsions, and multiple emulsions with highly fluorinated phase or membrane components.…”

Recent Advances in Solid‐State MAS NMR Methodology for Probing Structure and Dynamics in Polymeric and Supramolecular Systems

“…[70] Rotor-synchronised 1 H DQ MAS spectra of these semi-fluorinated dendrons with various electron-donor groups in the solid and LC phase have recently been published. [81] A related example is a discotic trisamide that consists of C 3 -symmetrical molecules with intramolecular hydrogen bonds that, at room temperature, form a discotic LC phase based on hexagonally ordered columns. [33,82] …”

Challenges and breakthroughs in recent research on self-assembly

“…Among them dendrimers make attractive structural units because the shape of the dendron units is relatively inflexible when compared with freely extending conventional polymers. Exemplary work has been presented in pioneering research by Percec and coworkers [552]. Recently, they reported self-assembly of semifluorinated dendrons attached through a flexible spacer to an electron-donor, which induced p-stacking of the donors in the center of a supramolecular helical pyramidal column.…”