Shi Zhichun,Wen Jiaxiang,Zhao Yingnan,Wang Jianjun,Li Jun,Zhao Ming,Teraguchi Masahiro,Aoki Toshiki,Kaneko Takashi
A novel substituted phenylacetylene with a pendant betulin derivative group was designed and synthesized successfully, and the chemical structure of the monomer was confirmed by nuclear magnetic resonance spectroscopy (NMR, 1 H, 13 C), high-resolution mass spectrometry (HRMS) and Fourier transform infrared spectroscopy (FTIR). The obtained monomer was further polymerized in an achiral [Rh(nbd)Cl] 2 /triethylamine (TEA) catalytic system, and the resulting polymer exhibited a strong Cotton effect at the main-chain absorption regions in the circular dichroism (CD) spectra. This one-handed helical backbone was induced by the chiral source on the side chain and maintained by the rigid betulin derivative pendant flats. Furthermore, the rigid betulin derivatives also contributed to the porous morphology and perfect thermal stability of the polymer. This study will provide a new method for preparing porous chiral polymers as efficient separation materials to solve practical issues.
Muyang Zhang,Yuming Zhou,Man He,Tao Zhang,Xiaohai Bu
The novel single-handed helical polysilanes (HPS), poly[di-n-hexylsilane-co-(methoxycarbonyl ethyl propyl ether)methylsilane] were synthesized by the Wurtz-type coupling of the chiral functional monomer, dichloro(methoxycarbonyl ethyl propyl ether)methylsilane (DCMMS). The monomer was prepared by the hydrosilylation reaction of methyl (S)-2-(allyloxy)propanoate. The chemical structure of HPS was confirmed by 1H, 13C and 29Si nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV-Vis) and circular dichroism (CD). The weight distributions and crystallinity of the polysilanes were demonstrated by gel permeation chromatography (GPC), differential scanning calorimetry (DSC) and polarized light microscopy (POM), respectively. The single-handed helical characterization and polymerization degree of the new-typed polysilanes could be controlled by the co-monomers of DCMMS and di-n-hexyldichlorosilane (DCDHS), respectively. Furthermore, the infrared emissivity values (0.598 at 8–14 μm) of HPS were investigated by an Infrared Emissometer.