The reaction of oxidorhenium() with dipodal and tripodal aroylhydrazines: formation of dinuclear and trinuclear aroylhydrazone-bridged rhenium() complexes

• Published in: New journal of chemistry 2020-05, Vol.44 (17), p.78-79
• Main Authors: Mukiza, Janvier, Blacque, Olivier, Habarurema, Gratien, Kampire, Edwige
• Format: Article
• Language: English
• Subjects: Acetone; Anions; Benzene; Chelates; Crystal structure; Crystallography; Density functional theory; Functional groups; Hydrocarbons; Imines; Infrared spectroscopy; Ligands; NMR spectroscopy; Rhenium
• ISSN: 1144-0546; 1369-9261
• DOI: 10.1039/d0nj00182a

The chemistry of aroylhydrazines has been attracting attention mainly due to the residual functional group, -CONH-NH 2 , which has important effects on hydrophilicity and has the potential to provide special interaction sites for targeting molecules. The reaction of a dipodal aroylhydrazine, typically isophthalohydrazide (isphz), with trans -[ReOX 3 (PPh 3 ) 2 ] in acetone led to the isolation of ligand-bridged oxidorhenium( v ) dinuclear complexes (μ-dphz)[ReOX 2 (PPh 3 )] 2 , (X = Cl ( 1 ), Br ( 2 ). The novel dianion dipodal aroylhydrazone Schiff base N ′ 1 , N ′ 3 -di(propan-2-ylidene)isophthalohydrazide (dphz 2− ) was formed by the condensation of acetone with isphz and coordinated to each of the [ReO] 3+ units as a monoanionic N,O-donor chelate, bridging via the dphz 2− dianion. The reaction of a tripodal aroylhydrazine, typically benzene-1,3,5-tricarbohydrazide (bthz), with trans -[ReOBr 3 (PPh 3 ) 2 ] in acetone led to the isolation of the ligand-bridged oxidorhenium( v ) trinuclear complex (μ-tbhz)[ReOBr 2 (PPh 3 )] 3 ( 3 ). The novel trianion tripodal aroylhydrazone Schiff base N ′ 1 , N ′ 3 , N ′ 5 -tri(propan-2-ylidene)benzene-1,3,5-tricarbohydrazide (tbhz 3− ) was also formed from the condensation of acetone with bthz and coordinated to each of the [ReO] 3+ units as a monoanionic N,O-donor chelate, bridging via the tbhz 3− trianion. The crystal structures, infra-red (IR), 1 H-NMR, and 31 P-NMR spectroscopy of the complexes are reported. In addition, the density functional theory (DFT) calculations and the chromatographic behavior of the synthesised complexes are studied. The chemistry of aroylhydrazines has been attracting attention mainly due to the residual functional group, -CONH-NH 2 , which has important effects on hydrophilicity and has the potential to provide special interaction sites for targeting molecules.