Copper(II) complexes with lignin model compound vanillin
Year: 2015
Type: article
Abstract: Three copper(II) coordination compounds with vanillinate ion trans-[Cu(C 8 H 7 O 3 ) 2 (H 2 O) 2 ].2H 2 O 1, [Cu(C 8 H 7 O 3 ) 2 (H 2 O) 2 ] 2 and [Cu(C 5 H 7 O 3 ) 2 (H 2 O) 2 ].2H 2 O 3 were synthesized and characterized. The structure analysis of air-unstable complex 1 reveals trans arrangement of two vanillinate ligands around copper(II) ion, coordinated via methoxy (Cu-03 2.3266(14) A) and deprotonated hydroxy group (Cu-04 1.9383(13) A). In the octahedral coordination sphere, two water molecules are also present (Cu-Owl 2.0113(15)A). Copper(II) ions in air-stable vanillinate complexes 2, 3 and la ([Cu(C 8 H 7 O 3 ) 2 (H 2 O) 2 ]; partially decomposed 1), that show very similar vibrational and electronic spectra, represent isolated paramagnetic centers (μ e f f > 1.73 BM). The most significant differences in IR spectra are above 3000 cm - 1 for la (partial decomposition of 1 and different H-bonding), and in electronic spectra for non-typical orange coloured 2 with respect to yellow-green la and 3.
Language: English
Subfield: Inorganic Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2471713828