A fluorescent organic nanotube assembled from novel p-phenylene ethynylene-based dicationic amphiphiles.
Novel π-extended conjugated amphiphiles composed of a hydrophilic section of two quaternary ammonium groups and p-phenylene ethynylene with adjustable alkyl chain hydrophobic section were prepared by a multistep synthesis. These dicationic amphiphiles showed good water solubility and formed a tubular assembly in water. The evidence for the nanotubular comes from direct optical and TEM observations. A strong π-π stacking interaction between neighboring molecules, as evidenced by the red-shift and self-quenching in fluorescence, is proposed for the self-assembly. At the same time, dehydration of the bromide led to strong counterion condensation in headgroups, which resulted in the small curvature structure of the nanotubes. A bilayer lamellar structural model for the organic nanotube is proposed, and a reasonable structural model based on the experimental XRD pattern, as well as cell constants, is proposed.
Department of Chemistry, National Taiwan University, Taipei 106, Taiwan.
Ai-Jan
AJ
Chen
I-Jui
IJ
Hsu
Wei-Yi
WY
Wu
Yu-Tse
YT
Su
Fu-Yu
FY
Tsai
Chung-Yuan
CY
Mou
D000480:Alkynes / Q000138:chemical synthesis* / Q000737:chemistry; D002412:Cations / Q000138:chemical synthesis / Q000737:chemistry; D018360:Crystallography, X-Ray; D004987:Ethers / Q000138:chemical synthesis* / Q000737:chemistry; D005456:Fluorescent Dyes / Q000138:chemical synthesis* / Q000737:chemistry; D057927:Hydrophobic and Hydrophilic Interactions; D008958:Models, Molecular; D015394:Molecular Structure; D043942:Nanotubes / Q000737:chemistry*; D010316:Particle Size; D013499:Surface Properties
D000480:Alkynes; D002412:Cations; D004987:Ethers; D005456:Fluorescent Dyes; C436384:phenyleneethynylene