Title: Microporous Cyclic Titanium-Oxo Clusters with Labile Surface Ligands

Authors: Chaowei Zhao,Ying-Zi Han,Shuqi Dai,Xumao Chen,Juanzhu Yan,Weijie Zhang,Haifeng Su,Shuichao Lin,Zichao Tang,Boon K. Teo,Nanfeng Zheng

Abstract:

By combining the use of ethylene glycol and monocarboxylic acid as surface ligands, a series of cyclic Ti-oxo clusters with permanent microporosity are successfully synthesized. With a cyclic {Ti32O16} backbone made of eight Ti4 cages arranged in a zigzag fashion, the clusters have a "donut" shape with inner diameter of 8.3 Å, outer diameter of 26.9 Å and height of 10.4 Å. While both inner and outer walls of the "donut" clusters are modified by double-deprotonated ethylene glycolates, their upper and lower surfaces are bound by carboxylates and mono-deprotonated ethylene glycolates. The clusters are readily packed into one-dimensional tubes which are further arranged in two different modes into crystalline microporous solids with surface areas over 660 m2/g. Moreover, the mono-deprotonated ethylene glycolates on the clusters are highly exchangeable by other alcohols, providing a nice platform for creating microporous solids or films with a wide variety of surface functionalities.

Full-Link:http://onlinelibrary.wiley.com/doi/10.1002/anie.201709096/full