N-alkyl salicylaldimine complexes: Infrared and PMR spectra of the ligands and vibrational frequencies of their metal(II) chelates

Synthesis and characterization of diorganotin(IV) complexes of tridentate Schiff bases: crystal structure of [N-(3-hydroxypyridine-2-yl)-5-chlorosalicylideneiminato]dimethyltin(IV)

“…This is in agreement with the literature values [27,28,[42][43][44]. The Schiff bases are apparently in the phenol-imine tautomeric form as the azomethine proton in a quinoid structure is known to exhibit a three-bond coupling to the NH proton [42][43][44][45][46][47][48]. The lack of such coupling in our case indicates that the phenol-imine tautomer predominates.…”

Synthesis and characterization of manganese(IV) and ruthenium(III) complexes derived from bis (2-hydroxy-1-naphthaldehyde)oxaloyldihydrazone

“…From the infrared spectral data discussed above, it is evident that the ligand binds to metal through naphtholate oxygen and hydrazide nitrogen either in the keto form or enol form. The (M-O) (naphtholic) [45][46][47] may be expected at higher frequencies than (M-O) (carbonyl) [48,49] for difference in bond order. On examining the spectra of the ligands and its manganese and ruthenium complexes below 600 cm À1 , the new band appearing in the 542-584 cm À1 region is tentatively assigned to (M-O)(naphtholate).…”

Synthesis, crystal structure, magnetic characterization and spectroscopic properties of a new dinuclear iron(III) complex asymmetrically bridged by a phenoxo and methoxo groups

“…The phenoxy and methoxy carbon atoms attached to the bridging oxygens are displaced on opposite sides of the bridging plane by 0.123(2) Å for C27 and 0.118(3) Å for C28, respectively. Spectroscopic properties The most significant effects of coordination on the vibrational spectrum of free salicylaldimine Schiff base ligands are observed and previously reported between ~1500 and ~1650 cm -1 [38][39][40]. This spectral region of the free ligand is attributed to the azomethinic ν(C-N) and phenolic ν(C-O) stretching modes, respectively.…”