TY - JOUR
T1 - Coordination studies of copper(II), cobalt(II) and iron(II) with isomeric pyridyl-tetrazole ligands
AU - Bond, Andrew D.
AU - Fleming, Adrienne
AU - Gaire, Jackie
AU - Kelleher, Fintan
AU - McGinley, John
AU - McKee, Vickie
AU - Sheridan, Ursula
N1 - Funding Information:
J.G. thanks the Postgraduate R&D Skills programme (Technological Sector Research, Strand I) and IT Tallaght Dublin for financial assistance. U.S. thanks NUIM for a John & Pat Hume Fellowship. A.D.B. is grateful to the Danish Natural Sciences Research Council and the Carlsberg Foundation for provision of the X-ray equipment.
PY - 2012/2/9
Y1 - 2012/2/9
N2 - The reaction of 2-(2H-tetrazol-5-yl)pyridine (L1) with 1,6-dibromohexane results in formation of the isomers 2-(6″-bromohexyl)-(1-tetrazol-5-yl) pyridine (L2) and 2-(6″-bromohexyl)-(2-tetrazol-5-yl)pyridine (L3). Coordination reactions of L2 and L3 with CuCl 2·2H 2O, Co(SCN) 2 and Fe(ClO 4) 2· H 2O yielded the strongly coloured solids [Cu(II)(L2)Cl 2] 2 (1), [Cu(II)(L3)Cl 2] 2 (2), [Co(II)(L2) 2(NCS) 2] (3), [Co(II)(L3) 2(NCS) 2] (4), [Fe(II)(L2) 2(H 2O) 2](ClO 4) 2 (5) and [Fe(II)(L3) 2(H 2O) 2](ClO 4) 2 (6), containing high-spin metal centres for the Co(II) and Fe(II) compounds. X-ray crystal structures were obtained for complexes 1-5. In each complex, ligands L2 and L3 coordinate to the metal centre through the pyridyl N atom and the 1-N site of the tetrazole ring, and the pyridyl-tetrazole ligand remains planar in all cases except 3. Complexes 1 and 2 comprise a central Cu 2Cl 2 dimeric core with Cu(II) in an essentially square-pyramidal coordination environment. Complexes 3 and 4 contain Co(II) in a distorted octahedral coordination environment. In 3, the pyridyl and tetrazole rings of L2 are twisted with respect to each other and the complex adopts a puckered conformation in its equatorial plane. Complex 5 contains water molecules coordinated to Fe(II) in the axial sites, which form hydrogen bonds to the perchlorate counter anions.
AB - The reaction of 2-(2H-tetrazol-5-yl)pyridine (L1) with 1,6-dibromohexane results in formation of the isomers 2-(6″-bromohexyl)-(1-tetrazol-5-yl) pyridine (L2) and 2-(6″-bromohexyl)-(2-tetrazol-5-yl)pyridine (L3). Coordination reactions of L2 and L3 with CuCl 2·2H 2O, Co(SCN) 2 and Fe(ClO 4) 2· H 2O yielded the strongly coloured solids [Cu(II)(L2)Cl 2] 2 (1), [Cu(II)(L3)Cl 2] 2 (2), [Co(II)(L2) 2(NCS) 2] (3), [Co(II)(L3) 2(NCS) 2] (4), [Fe(II)(L2) 2(H 2O) 2](ClO 4) 2 (5) and [Fe(II)(L3) 2(H 2O) 2](ClO 4) 2 (6), containing high-spin metal centres for the Co(II) and Fe(II) compounds. X-ray crystal structures were obtained for complexes 1-5. In each complex, ligands L2 and L3 coordinate to the metal centre through the pyridyl N atom and the 1-N site of the tetrazole ring, and the pyridyl-tetrazole ligand remains planar in all cases except 3. Complexes 1 and 2 comprise a central Cu 2Cl 2 dimeric core with Cu(II) in an essentially square-pyramidal coordination environment. Complexes 3 and 4 contain Co(II) in a distorted octahedral coordination environment. In 3, the pyridyl and tetrazole rings of L2 are twisted with respect to each other and the complex adopts a puckered conformation in its equatorial plane. Complex 5 contains water molecules coordinated to Fe(II) in the axial sites, which form hydrogen bonds to the perchlorate counter anions.
KW - Coordination chemistry
KW - Pyridyl-tetrazole ligand
KW - Transition metal
KW - X-ray crystal structures
UR - http://www.scopus.com/inward/record.url?scp=84855849419&partnerID=8YFLogxK
U2 - 10.1016/j.poly.2011.11.038
DO - 10.1016/j.poly.2011.11.038
M3 - Article
AN - SCOPUS:84855849419
SN - 0277-5387
VL - 33
SP - 289
EP - 296
JO - Polyhedron
JF - Polyhedron
IS - 1
ER -