TY - JOUR
T1 - Structural study and solution integrity of dioxomolybdenum(VI) complexes with tridentate Schiff base and azole ligands
AU - Zhang, Cungen
AU - Rheinwald, Gerd
AU - Lozan, Vasile
AU - Wu, Biao
AU - Lassahn, Paul Gerhard
AU - Lang, Heinrich
AU - Janiak, Christoph
PY - 2002
Y1 - 2002
N2 - Four new molybdenum complexes [Mo VIO 2(L 1)(Him)] (1), [Mo VIO 2(L 1)(3-MepzH] (2), [Mo VIO 2(L 2)(3-MepzH)] (3), and [(Mo VIO 2) 2(μ-L 3)(MeOH) 2] (4) were synthesized and characterized by IR, NMR, ESI-MS, and single-crystal structure analysis [H 2L 1 = 2-(salicylideneamino)-2-methyl-1-propanol, H 2L 2 = 2-(3-methoxysalicylideneamino)-2-methyl-1-propanol, H 4L 3 = 1,7-bis(salicylidene)dihydrazide malonic acid, Him = imidazole and 3-MepzH = 3-methylpyrazole]. In all four structures the molybdenum atom has a distorted octahedral coordination with the three meridional donor atoms from the Schiff base di- or tetraanion (L 1,2) 2-/(L 3) 4- and one oxo group occupying the sites of the equatorial plane. The other oxo group and the azole or methanol molecule occupy the apical sites. In 1-3 two centrosymmetrically related molecules form a hydrogen-bonded pair through the (azole)N-H···O(alkoxo) interaction. Additional crystal packing appears to be controlled mostly by π stacking between the aromatic rings of the salicyl moiety. ESI-MS investigations reveal that the integrity of complexes 1-4 is largely retained in methanol solution. At the same time evidence is provided that di- to tetranuclear oligomers of formula [{Mo VIO 2(L)} x] and [{Mo VIO 2(L)} x(3-MepzH)] with L = L 1,L 2, x = 2,3,4 are present simultaneously with 2 and 3 in methanol solution, respectively the tetranuclear species [{(Mo VIO 2) 2(L 3)} 2] with 4.
AB - Four new molybdenum complexes [Mo VIO 2(L 1)(Him)] (1), [Mo VIO 2(L 1)(3-MepzH] (2), [Mo VIO 2(L 2)(3-MepzH)] (3), and [(Mo VIO 2) 2(μ-L 3)(MeOH) 2] (4) were synthesized and characterized by IR, NMR, ESI-MS, and single-crystal structure analysis [H 2L 1 = 2-(salicylideneamino)-2-methyl-1-propanol, H 2L 2 = 2-(3-methoxysalicylideneamino)-2-methyl-1-propanol, H 4L 3 = 1,7-bis(salicylidene)dihydrazide malonic acid, Him = imidazole and 3-MepzH = 3-methylpyrazole]. In all four structures the molybdenum atom has a distorted octahedral coordination with the three meridional donor atoms from the Schiff base di- or tetraanion (L 1,2) 2-/(L 3) 4- and one oxo group occupying the sites of the equatorial plane. The other oxo group and the azole or methanol molecule occupy the apical sites. In 1-3 two centrosymmetrically related molecules form a hydrogen-bonded pair through the (azole)N-H···O(alkoxo) interaction. Additional crystal packing appears to be controlled mostly by π stacking between the aromatic rings of the salicyl moiety. ESI-MS investigations reveal that the integrity of complexes 1-4 is largely retained in methanol solution. At the same time evidence is provided that di- to tetranuclear oligomers of formula [{Mo VIO 2(L)} x] and [{Mo VIO 2(L)} x(3-MepzH)] with L = L 1,L 2, x = 2,3,4 are present simultaneously with 2 and 3 in methanol solution, respectively the tetranuclear species [{(Mo VIO 2) 2(L 3)} 2] with 4.
KW - ESI-MS
KW - Hydrogen bonding
KW - Molybdenum
KW - Schiff base
KW - Stacking
KW - π
UR - http://www.scopus.com/inward/record.url?scp=0036305210&partnerID=8YFLogxK
U2 - 10.1002/1521-3749(200206)628:6<1259::AID-ZAAC1259>3.0.CO;2-Q
DO - 10.1002/1521-3749(200206)628:6<1259::AID-ZAAC1259>3.0.CO;2-Q
M3 - Article
AN - SCOPUS:0036305210
SN - 0044-2313
VL - 628
SP - 1259
EP - 1268
JO - Zeitschrift fur Anorganische und Allgemeine Chemie
JF - Zeitschrift fur Anorganische und Allgemeine Chemie
IS - 6
ER -