Zhongqiang Liu
Synthesis of square planar geometry cation connecting polymers
Mimic of the self-assembled H-bond connecting polymers
Most the self-assembled polymers are connected by H bond, which is non-covalent and lesser stable than valent one.
We design to explore the characteristic strong bonding of cupper(II) cation and α, β ketone (ACAC). Through synthesis
of molecules with 2 or 3acac, we could make a linear or planar super-molecule and study their characteristics, intending to find possible new materials.
I have synthesized the following molecules:
If the strategy works, the 3acac molecule could form a disc and the 2acac could form a thread. I have finished the complexion with copper cation, but due to the insolubility of the complex, it is not easy to detect their structure. So I decide to change copper to platinum, which will not influence NMR detection.
Anion Host
After the discovery of crown ether, cation host has been well developed. However the anion host has no such luck, due to the its apparent difference. Compared with cations, anions have the following different characteristics,
1 The anions are bulkier and have larger ionic radii.
2 The shapes vary much, such as spherical, planar, tetrahedral and linear forms.
3 More strongly solved. That is a severe free energy penalty.
For crown ether, the macro cycle effect plays a very important role. Due to the crown shape, the electron lone pairs of Oxygen are conflicting each other at the center of crown ether. That raises the energy of un-bind crown ether. After it binds a cation, such as Na, it lowers the free energy enough to give high binding constant.
We are wondering that whether we could exploit this and find a mimic of crown ether.
Zhongqiang Liu is the second year graduate student majoring in organic chemistry. He received his BS degree from USTC, China. He likes sports and literature, such as swimming, shaping and playing badmiton.