Premium
Functionalization of Titanium Oxide Cluster Ti 17 O 24 (O i C 3 H 7 ) 20 with Catechols: Structures and Ligand‐Exchange Reactivities
Author(s) -
Liu Caiyun,
Hu Junyi,
Zhu Feng,
Zhan Jinhua,
Du Lin,
Tung ChenHo,
Wang Yifeng
Publication year - 2019
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.201902601
Subject(s) - surface modification , raman spectroscopy , denticity , protonation , ligand (biochemistry) , oxide , reactivity (psychology) , titanium , crystallography , supramolecular chemistry , chemistry , titanium oxide , cluster (spacecraft) , materials science , stereochemistry , crystal structure , organic chemistry , physics , ion , medicine , biochemistry , receptor , alternative medicine , programming language , pathology , computer science , optics
The functionalization of Ti 17 O 24 (O i C 3 H 7 ) 20 (Ti 17 ) with substituted catechols is studied by using crystallography, Raman spectroscopy, and stopped‐flow kinetics. The knowledges on the number of accessible functionalities, their exact location correlated with their Raman assignment, and the kinetic parameters are acquired. A catecholate ligand binds to a five‐coordinated surface Ti of Ti 17 (denoted as Ti a site) adopting the mono‐protonated, chelate‐bidentate binding mode, whereas it binds to a six‐coordinated surface‐Ti (denoted as Ti b site) adopting the mono‐dentate mode. With low numbers of equivalents of added catechols the Ti a sites show higher reactivity than the Ti b sites toward functionalization. Two binding modes may co‐exist and equilibrate in solution. Our results also imply that at most eight of the twenty O i C 3 H 7 ligands of Ti 17 are exchangeable without damage of the core structure. The kinetic studies point out that the ligand‐exchange reaction is second order and occurs very fast. The current findings are helpful for the controlled functionalization of Ti 17 and other Ti oxide clusters, and the further application of them as building blocks in supramolecular chemistry for the assembly of well‐defined organic–inorganic hybrid materials.