TY - JOUR
T1 - Facile synthesis of Cu(II) complexes of monocondensed N,N,N donor Schiff base ligands
T2 - Crystal structure, spectroscopic and magnetic properties
AU - Chattopadhyay, Shouvik
AU - Ray, Mau Sinha
AU - Drew, Michael G.B.
AU - Figuerola, Albert
AU - Diaz, Carmen
AU - Ghosh, Ashutosh
N1 - Funding Information:
This work was supported by CSIR, India (Fellowship for S.C Sanction No. 9/28(614)/2003-EMR-I). We thank the Spanish government (Grant BQU2003-00539) and EPSRC, the University of Reading for funds for the image plate system.
PY - 2006/7/31
Y1 - 2006/7/31
N2 - Four new copper(II) complexes, [(CuL1N3)2](ClO4) 2 (1), [(CuL2N3)2](ClO4) 2 (2), [CuL3(N3)(ClO4)]n (3) and [CuL4(μ-1,1-N3)(μ-1,3-N3) (ClO4)]n (4) where L1 = N1-pyridin-2-yl-methylene-propane-1,3-diamine, L2 = N1-(1-pyridin-2-yl-ethylidene)propane-1,3-diamine, L3 = N1-(1-pyridin-2-yl-ethylidene)ethane-1,2-diamine and L4 = N1-(1-pyridin-2-yl-ethylidene)propane-1,2-diamine are four tridentate N,N,N donor Schiff base ligands, have been derived and structurally characterized by X-ray crystallography. Compounds 1 and 2 consist of double basal-apical end-on (EO) azide bridged dinuclear CuII complexes with square-pyramidal geometry. In complex 3 the square planar mononuclear [CuL3(N3)] units are linked by weakly coordinated perchlorate ions in the axial positions of CuII to form a one-dimensional chain. Two such chains are connected by hydrogen bonds involving perchlorate ions and azide groups. Compound 4 consists of 1-D chains in which the CuII ions with a square-pyramidal geometry are alternately bridged by single EO and end-to-end (EE) azido ligands, both adopting a basal-apical disposition. Variable temperature (300-2 K) magnetic susceptibility measurements and magnetization measurements at 2 K have been performed. The results reveal that complexes 1 and 2 are antiferromagnetically coupled through azido bridges (J = -12.18 ± 0.09 and -4.43 ± 0.1 cm-1 for 1 and 2, respectively). Complex 3 shows two different magnetic interactions through the two kinds of hydrogen bonds; one is antiferromagnetic (J1 = -9.69 ± 0.03 cm-1) and the other is ferromagnetic (J2 = 1.00 ± 0.01 cm-1). From a magnetic point of view complex 4 is a ferromagnetic dinuclear complex (J = 1.91 ± 0.01 cm-1) coupled through the EO bridge only. The coupling through the EE bridge is practically nil as the N(azido)-CuII (axial) distance (2.643 Å) is too long.
AB - Four new copper(II) complexes, [(CuL1N3)2](ClO4) 2 (1), [(CuL2N3)2](ClO4) 2 (2), [CuL3(N3)(ClO4)]n (3) and [CuL4(μ-1,1-N3)(μ-1,3-N3) (ClO4)]n (4) where L1 = N1-pyridin-2-yl-methylene-propane-1,3-diamine, L2 = N1-(1-pyridin-2-yl-ethylidene)propane-1,3-diamine, L3 = N1-(1-pyridin-2-yl-ethylidene)ethane-1,2-diamine and L4 = N1-(1-pyridin-2-yl-ethylidene)propane-1,2-diamine are four tridentate N,N,N donor Schiff base ligands, have been derived and structurally characterized by X-ray crystallography. Compounds 1 and 2 consist of double basal-apical end-on (EO) azide bridged dinuclear CuII complexes with square-pyramidal geometry. In complex 3 the square planar mononuclear [CuL3(N3)] units are linked by weakly coordinated perchlorate ions in the axial positions of CuII to form a one-dimensional chain. Two such chains are connected by hydrogen bonds involving perchlorate ions and azide groups. Compound 4 consists of 1-D chains in which the CuII ions with a square-pyramidal geometry are alternately bridged by single EO and end-to-end (EE) azido ligands, both adopting a basal-apical disposition. Variable temperature (300-2 K) magnetic susceptibility measurements and magnetization measurements at 2 K have been performed. The results reveal that complexes 1 and 2 are antiferromagnetically coupled through azido bridges (J = -12.18 ± 0.09 and -4.43 ± 0.1 cm-1 for 1 and 2, respectively). Complex 3 shows two different magnetic interactions through the two kinds of hydrogen bonds; one is antiferromagnetic (J1 = -9.69 ± 0.03 cm-1) and the other is ferromagnetic (J2 = 1.00 ± 0.01 cm-1). From a magnetic point of view complex 4 is a ferromagnetic dinuclear complex (J = 1.91 ± 0.01 cm-1) coupled through the EO bridge only. The coupling through the EE bridge is practically nil as the N(azido)-CuII (axial) distance (2.643 Å) is too long.
KW - Azide bridged
KW - Cu complexes
KW - Magnetic properties
KW - N,N,N donor tridentate Schiff base
KW - Perchlorate bridged
KW - X-ray structure
UR - http://www.scopus.com/inward/record.url?scp=33745905971&partnerID=8YFLogxK
U2 - 10.1016/j.poly.2006.01.024
DO - 10.1016/j.poly.2006.01.024
M3 - Article
AN - SCOPUS:33745905971
SN - 0277-5387
VL - 25
SP - 2241
EP - 2253
JO - Polyhedron
JF - Polyhedron
IS - 11
ER -