Furan-Containing Oligoaryls and Polymers: Synthesis and Photophysics
Date Issued
2007
Date
2007
Author(s)
Chou, Chih-Ming
DOI
zh-TW
Abstract
A range of oligoaryls having alternating para- or meta-benzene-furan rings is synthesized by rapid convergent/divergent method from the annlation of a propargylic dithioacetal and an aldehyde having a propargylic dithioacetal moiety as the substituent. This route provides a useful procedure toward the synthesis of monodisperse oligoaryls without repetitive units. Systematic investigation on the photophysical properties and molecular folder phenomenon of these oligomers are also explored.
A series of dithiolated alternating benzene-furan oligoaryls was synthesized. IRAS (infrared reflection-absorption spectroscopy) and STM (scanning tunneling microscopy) experiments revealed that single-component monolayers of these oligoaryls have lattice packing of crystalline by pi-pi interaction and each distance between two single molecules is about 0.51 nm. The conductance of single molecule was decreased with the conjugated length of alternating benzene-furan oligoaryls increased.
In addition, a series of double stranded polymers by using furan-containing oligoaryls as linkers was synthesized. Conformational change of the norbornene moiety after ROMP (ring opening metathesis polymerization) lead chormophores aggregated and quenched the fluorescent intensity. The first oxidation potential of polymers were conformably lower than corresponding monomers, and the difference of first oxidation potential between monomer and polymer was increased with the conjugated length of chormophores increased.
Subjects
分流法
匯集法
苯環呋
喃交錯寡聚物
convergent
divergent
alternating benzene-furan oligoaryls
Type
thesis