TY - JOUR
T1 - Effect of Polyether Ligands on Stabilities and Mass Transport Properties of a Series of Gadolinium(III) β-Diketonate Complexes
AU - Baxter, Ian
AU - Drake, Simon R.
AU - Hursthouse, Michael B.
AU - Abdul Malik, K. M.
AU - McAleese, John
AU - Otway, David J.
AU - Plakatouras, John C.
PY - 1995/3/1
Y1 - 1995/3/1
N2 - The reaction of [Gd(tmhd)3]2 (1) (tmhd-H = 2,2,6,6-tetramethylheptane-3,5-dione) with a selected range of chelating O-donors such as, mono- {CH3OCH2CH2OCH3}, di- {CH3(OCH2CH2OCH3}, tri- {CH3(OCH2CH2)3OCH3}, tetra- {CH3(OCH2CH2)4OCH3}, and heptaglyme {CH3(OCH2CH2)7OCH3} in n-hexane at room temperature yielded the compounds [Gd(tmhd)3(monoglyme)] (2), [Gd(tmhd)3(diglyme)] (3), [{Gd(tmhd)3}2(triglyme)] (4), [{Gd-(tmhd)3}2(tetraglyme)] (5), and [{Gd(tmhd)3}2(heptaglyme)] (6), respectively. The complexes are either monomers (2, 3) or dimers (1, 4–6) and have been characterized by microanalyses, solution cryoscopy in benzene, FT IR, mass spectrometry, and sublimation, TGA, and DSC studies. Complexes 1, 2, 5, and 6 have also been characterized by X-ray crystallography. 1 and 6 both crystallize in the monoclinic space group P21/n, with a = 12.228(2) Å, b = 27.615(2) Å, c = 21.843(11) Å, and β = 105.27(6)° (1) and a = 11.773(2) Å, b = 18.712(3) Å, c = 21.610(3) Å, and β = 103.53(1)° (6). 2 and 5 crystallize in the triclinic space group P1 with a = 10.814(2) Å, b = 12.141(3) Å, c = 16.534(2) Å, α = 83.90(1)°, β = 88.20(1)°, and γ = 71.85(1)° (2) and a = 11.934(2) Å, b = 19.478(4) Å, c = 20.508(10) Å, α = 99.25(1)°, β = 106.94(2)°, and γ = 104.76(1)°, (5). The gadolinium ion shows a seven-coordinate distorted monocapped trigonal prismatic geometry in 1 and an eight coordinate square antiprismatic geometry in the other compounds. In 2 the monoglyme acts as bidentate chelating ligand. The tetraglyme and heptaglyme molecules in complexes 5 and 6, respectively, act as chelating as well as bridging ligands, utilizing four of their available oxygen atoms for coordination. All these compounds are air and water stable, and those with the longer glymes have good volatilities and thermal stabilities, as demonstrated by sublimation, TGA, and DSC studies.
AB - The reaction of [Gd(tmhd)3]2 (1) (tmhd-H = 2,2,6,6-tetramethylheptane-3,5-dione) with a selected range of chelating O-donors such as, mono- {CH3OCH2CH2OCH3}, di- {CH3(OCH2CH2OCH3}, tri- {CH3(OCH2CH2)3OCH3}, tetra- {CH3(OCH2CH2)4OCH3}, and heptaglyme {CH3(OCH2CH2)7OCH3} in n-hexane at room temperature yielded the compounds [Gd(tmhd)3(monoglyme)] (2), [Gd(tmhd)3(diglyme)] (3), [{Gd(tmhd)3}2(triglyme)] (4), [{Gd-(tmhd)3}2(tetraglyme)] (5), and [{Gd(tmhd)3}2(heptaglyme)] (6), respectively. The complexes are either monomers (2, 3) or dimers (1, 4–6) and have been characterized by microanalyses, solution cryoscopy in benzene, FT IR, mass spectrometry, and sublimation, TGA, and DSC studies. Complexes 1, 2, 5, and 6 have also been characterized by X-ray crystallography. 1 and 6 both crystallize in the monoclinic space group P21/n, with a = 12.228(2) Å, b = 27.615(2) Å, c = 21.843(11) Å, and β = 105.27(6)° (1) and a = 11.773(2) Å, b = 18.712(3) Å, c = 21.610(3) Å, and β = 103.53(1)° (6). 2 and 5 crystallize in the triclinic space group P1 with a = 10.814(2) Å, b = 12.141(3) Å, c = 16.534(2) Å, α = 83.90(1)°, β = 88.20(1)°, and γ = 71.85(1)° (2) and a = 11.934(2) Å, b = 19.478(4) Å, c = 20.508(10) Å, α = 99.25(1)°, β = 106.94(2)°, and γ = 104.76(1)°, (5). The gadolinium ion shows a seven-coordinate distorted monocapped trigonal prismatic geometry in 1 and an eight coordinate square antiprismatic geometry in the other compounds. In 2 the monoglyme acts as bidentate chelating ligand. The tetraglyme and heptaglyme molecules in complexes 5 and 6, respectively, act as chelating as well as bridging ligands, utilizing four of their available oxygen atoms for coordination. All these compounds are air and water stable, and those with the longer glymes have good volatilities and thermal stabilities, as demonstrated by sublimation, TGA, and DSC studies.
UR - https://www.scopus.com/pages/publications/0000103527
U2 - 10.1021/ic00110a016
DO - 10.1021/ic00110a016
M3 - Article
AN - SCOPUS:0000103527
SN - 0020-1669
VL - 34
SP - 1384
EP - 1394
JO - Inorganic Chemistry
JF - Inorganic Chemistry
IS - 6
ER -