A <i>μ<sub>4</sub></i>‐Oxo Bridged Tetranuclear Zinc Complex as an Efficient Multitask Catalyst for CO<sub>2</sub> Conversion
Raman Kumar, Subash Chandra Sahoo, Prasant Kumar Nanda
Abstract
Abstract A tetranuclear zinc complex having formula [Zn 4 (L) 4 ( μ 2 ‐OH 2 ) 2 ( μ 4 ‐O)]⋅2TEAH⋅DMF⋅4H 2 O ( 1 ) has been synthesized from a benzothiazole based schiff base ligand. The complex was characterized by various spectroscopic and analytical techniques along with single crystal X‐ray diffraction (SCXRD) study. The crystal structure of the complex reveals that, there is formation of a tetranuclear dianionic core having metal centers in distorted trigonal bipyramidal (TBP) geometry supported by a μ 4 ‐oxo and two μ 2 ‐aqua bridgings. The μ 4 ‐oxo acquires a special position, connecting to the zinc centers in a distorted tetrahedral ( T d ) fashion is mainly responsible for the higher nuclearity of the complex. The complex 1 exhibited multitask catalytic ability for CO 2 utilization. It acts as an efficient catalyst for the conversion of various epoxides to cyclic carbonates as well as mimics carbonic anhydrase (CA) metalloenzyme. Hydrolysis of para‐ nitrophenyl acetate ( p‐ NPA) was used as a model reaction to evaluate the CA activity. The complex also catalyzes the formation of bicarbonate (HCO 3 − ) from CO 2 by converting CaCl 2 to CaCO 3 .