Table 1. Assignment of the Infrared Spectra Values of Maltol, 1, Ethylmaltol, and 2. Additional Shifting upon Ligand Coordination to Magnesium is Also Provided.

complex	IR frequency (cm–1)	assignment	change (cm–1)
maltol	3260	ν(OH), C–OH
	1655	ν(C=O)
	1621	ν(C=O)
1	3435	v(OH), H2O
	3264	ν(OH), C–OH	4
	1655	ν(C=O)
	1617	ν(C=O)	4
ethylmaltol	3369	ν(OH), C–OH
	1617	ν(C=O)
	1525	ν(C=O)
2	3447	ν(OH), H2O