Synthesis, spectroscopic [IR, (1H, 13C, 27Al) NMR] and mass spectrometric studies of aluminium(III) complexes containing O- and N-chelating Schiff bases

Abstract

Reactions of aluminium isopropoxide with 2-(o-hydroxyphenyl)-benzoxazole (pboxH) and salicylidene-4-chloroaniline (spcaH) in different molar ratios in benzene solution afforded the complexes of the types [(μ-OPr i ) 2 Al 2 (pbox) 2 (OPr i ) 2 ] 1, [Al(OPr i )(pbox) 2 ] 2, [Al(pbox) 3 ] 3, [(μ-OPr i ) 2 Al 2 (spca) 2 (OPr i ) 2 ] 4, [Al(OPr i )(spca) 2 ] 5 and [Al(spca) 3 ] 6. All these colored solid complexes are soluble in common organic solvents and were characterized by elemental (C, H, N and Al) analysis, spectroscopic [IR ( 1 H, 13 C and 27 Al) NMR] and mass spectrometric studies. On the basis of these studies, plausible structures have been tentatively proposed for these complexes.

DBD plasma‐assisted coating of metal alkoxides on sulfur powder for Li–S batteries

“…In addition, it is also possible that only some of the aluminum atoms of the coating are incorporated within the alumina. The main peaks between –10 and 5 ppm are attributed to octahedral alumina and are in agreement with the simulated results reported in the literature 50–52 . However, the signals attributed to alumina are broader, which indicates a lower degree of chain length.…”

“…NMR analysis of the alumina‐based coating is very challenging and the literature is very limited concerning the effect of plasma‐deposited coatings, making a full identification of the coating difficult. The signals of alumina can be observed in the spectrum at chemical shift positions (in ppm) expected from the literature 50–52 . However, the signals are weak, confirming that the coating is relatively thin (nanocoating).…”

“…The signals of alumina can be observed in the spectrum at chemical shift positions (in ppm) expected from the literature. [50][51][52] However, the signals are weak, confirming that the coating is relatively thin (nanocoating). In addition, it is also possible that only some of the aluminum atoms of the coating are incorporated within the alumina.…”

“…The main peaks between -10 and 5 ppm are attributed to octahedral alumina and are in agreement with the simulated results reported in the literature. [50][51][52] However, the signals attributed to alumina are broader, which indicates a lower degree of chain length. This reveals that, as expected, the plasma-polymerized metal oxidebased coating presents certain inhomogeneities at the micrometric scale compared to coatings obtained using standard chemical/electrochemical methods.…”

Synthesis, spectroscopic characterization and computational studies of Schiff base complexes of tin(IV) chloride

“…During the past decades, a number of molecular addition complexes of SnCl 4 with N O donor ligands have been reported (Chen et al, 2013;Teoh et al, 1997) while its reaction with sodium salt of bidantate salicylidiminte derivative ligand has been investigated to a very limited extent (Dubey and Singh, 2013). Keeping all the mention fact in mind and our persistent interest in Schiff base derived from salicylaldehyde (Dubey et al, 2011a;Dubey et al, 2012a) with their main group metal complexes (Dubey and Singh, 2015;Dubey et al, 2011b;Dubey et al, 2012b;Kushwaha et al, 2017), we report herein synthesis and spectroscopic characterization of some tin(IV) complexes with salicyaldehyde and o-vanillin derived Schiff base ligands. Density functional theory (DFT) calculation of ligand and complexes were also carried out to obtain optimized molecular geometry and other quantum mechanical parameters.…”