Physico-chemical properties of the first metal compound of di-2-pyridylketone p-nitrophenoxyacetic acid hydrazone (dpknxh), fac-Re(CO)₃(κ²-N_py,N_py-dpknxh)Cl

Abstract

Di-2-pyridyl ketone p-nitrophenoxyacetic acid hydrazone (1), obtained from acid-catalyzed condensation of di-2-pyridyl ketone (dpk) with p-nitrophenoxyacetic acid hydrazide, reacts with Re(CO)₅Cl in refluxing toluene to form fac-Re(CO)₃(κ²-N_py,N_py-dpknxh)Cl (2). 1 and 2 were identified from the results of their elemental analyses, spectroscopic and electrochemical properties. X-ray structural analysis on single crystals of 1 and 2 grown from CH₃CN solutions and fac-Re(CO)₃(κ²-N_py,N_py-dpknxh)Cl·DMSO (3) grown from a DMSO solution of 2 confirmed their identities. Spectrophotometric titrations of protophilic solutions of 2 with protophilic solutions of NaBX₄ (X = H or F) divulged inter-conversion between the high- and low-energy ILCT transitions of 2 and its solvated complex. Substrates in low concentrations can be detected and determined using protophilic solutions of 2. Electrochemical measurements on 1 and 2 disclosed irreversible redox transformations leading to decomposition of 1 and 2 following the first electron transfer.

Graphical Abstract

Keywords:

• Rhenium
• Di-2-pyridyl ketone p-nitrophenoxyacetic acid hydrazone
• X-ray
• spectroscopy
• electrochemistry

Acknowledgements

The author wishes to acknowledge Toni Johnson and Ordel Brown for technical assistance.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the The University of the West Indies.