Journal
JOURNAL OF MOLECULAR LIQUIDS
Volume 302, Issue -, Pages -Publisher
ELSEVIER
DOI: 10.1016/j.molliq.2020.112590
Keywords
Copper; Coordination compounds; Complexes; Schiff base; Hydrazone; Alcohol oxidation; Density Functional Theory (DFT); Green chemistry; Environmental chemistry
Funding
- National Science Center Poland (grant PRELUDIUM) [2015/17/N/ST5/01973]
Ask authors/readers for more resources
Green and sustainable chemistry approaches necessitate an ongoing investigation towards new, environmentally benign and selective catalysts. We have thus prepared a new benzothiazole-scaffolded hydrazone Schiff base ligand L and coordinated it with copper(II) ions leading to five different complexes, the form of which in the solid state is counterion-dependent. Nitrate, chloride and trifiate anions lead to monometallic species, whereas utilization of sulfates and tetrafluoroborates is responsible for the formation of bimetallic assemblies. The catalytic efficiency of synthesized compounds was shown in Cu-TEMPO (2,2,6,6-tetramethyl-l-piperidinoxyl) aerobic oxidation of activated alcohols resulting in good to excellent conversions and 100% selectivity to form the corresponding aldehydes. Considering the experimental results and Density Functional Theory calculations we propose two most plausible reaction mechanisms that further corroborate the enhanced activity of bimetallic species. It appears that the tridentate character of the ligand sacrifices some of the overall catalytic efficiency for the selectivity of the process. Aqueous reaction medium, low catalyst loading, air as oxidant and exclusive oxidative selectivity render these Cu ll complexes promising candidates for further improvement. (C) 2020 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available