27Al, 15N, 13C and 1H NMR spectra and negative-ion electrospray mass spectra of the 2:1 aluminium(III) complexes of azo dyes derived from anthranilic acid

The 27Al, 15N, 13C and 1H NMR spectra in DMSO and mass spectra of 2:1 aluminium(III) complexes (1b¯4b) derived from anthranilic acid azo coupling products with 4-tert.butylphenol (1a), 2-naphthol (2a) acetoacetanilide (3a) 3-methyl-1phenylpyrazol-5-one (4a) were measured and analysed. It was found that the aluminium atom was six-coordinated, being bound to two oxygens and the nitrogen originating from anthranilic acid.