An X-ray crystallographic study demonstrated that the tris complex of Al
3+ with 2-methyl-8-quinolinol (Hmq), [Al(mq)
3], had a discrete octahedral geometry in a meridional configuration with respect to mq
- the Al-N bonds were appreciably elongated. In organic solvents, the complex reacted with water to give a lower species of a μ-oxo dimer, [Al
2O(mq)
4], and a protonated ligand, depending on the concentrations of water and of excess ligand. None of Cl
- Br
- I
- ClO
4-, and CH
3COO
- showed any reactions with [Al(mq)
3]. The anions having high affinities to Al
3+, such as H
2PO
4- and F
- replaced all the ligand. The anion having a lower affinity, HSO
4-, exclusively formed a mixed-ligand complex of [Al(mq)
2HSO
4], which had a more intense fluorescence than the others. In contrast, the corresponding 8-quinolinol (Hq) complex, [Alq
3], showed no reactions with any anions.
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