312610-28-9Relevant academic research and scientific papers
The synthesis of calix[4]crown based dendrimer
Bu, Jian-Hua,Zheng, Qi-Yu,Chen, Chuan-Feng,Huang, Zhi-Tang
, p. 897 - 902 (2005)
A second generation of dendrimer with calixcrown as repeat unit was first synthesized. Its structure and conformation was determined by 1H NMR and MALDI-TOF mass spectra.
Helical nanostructures of an optically active metal-free porphyrin with four optically active binaphthyl moieties: Effect of metal-ligand coordination on the morphology
Lu, Jitao,Wu, Lizhen,Jiang, Jianzhuang,Zhang, Xiaomei
, p. 4000 - 4008 (2010)
An optically active metal-free porphyrin (1) with four chiral binaphthyl units attached at the meso-phenyl substituents through crown ether moieties has been designed, synthesized, and characterized. Its self-assembly behavior in the absence and presence of K+ was comparatively investigated by electronic absorption and circular dichroism (CD) spectra, transmission electron microscopy (TEM), scanning electron microscopy (SEM), atom force microscopy (AFM), and energy-dispersive X-ray (EDX) spectroscopy. In the absence of K +, metal-free porphyrin self-assembles into nanoparticles depending mainly on the van der Waals interaction among neighboring metal-free molecules. In the presence of K+, additionally formed metal-ligand K-O crown coordination bonds between K+ and crown units of (R)-and (S)-1 molecules, together with chiral discrimination of chiral side chains and intermolecular van der Waals interactions, induce a righthanded and left-handed helical arrangement in a stack of (R)-and (S)-1 molecules, respectively, with an ordered head-to-tail internal molecular arrangement. This then further hierarchically self-assembles into highly ordered fibrous nanostructures with a helicity opposite to that of the original porphyrin stack. This clearly reveals the effect of the metal-ligand coordination bonding interaction on the morphology and handedness of self-assembled nanostructures.
