Rigid oligonaphthalenediimide rods as transmembrane anion-pi slides.
We report the design, synthesis, and evaluation of rigid oligonaphthalenediimide (O-NDI) rods that are expected to act as transmembrane anion-pi slides. Studies in fluorogenic large unilamellar egg yolk phosphatidylcholine vesicles reveal that rigid O-NDI rods mediate anion-selective transport with a rare halide VI selectivity sequence (Cl- > F- > Br- > I-). This and decreasing activity, selectivity, and halide sequence with increasing positive charge of the rod termini support the occurrence of anion-pi interactions. A strong anomalous mole fraction effect in Cl-/I- mixtures is in agreement with the existence of multiple active sites along the anion-pi slide and multi-anion hopping as a mechanism of transport. The strong inverted NDI quadruple moment found by DFT calculations is in excellent agreement with these results.
Gorteau
Virginie
V
Department of Organic Chemistry, University of Geneva, Geneva, Switzerland.
Bollot
Guillaume
G
Mareda
Jiri
J
Perez-Velasco
Alejandro
A
Matile
Stefan
S
D000838:Anions; D007094:Imides; D008958:Models, Molecular; D009281:Naphthalenes; D010618:Phenanthrolines / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*
D000838:Anions; D007094:Imides; D009281:Naphthalenes; D010618:Phenanthrolines; D011108:Polymers; C542131:naphthalenediimide