Three kinds of copper(II) azide complexes have been synthesised in excellent yields by reacting C... more Three kinds of copper(II) azide complexes have been synthesised in excellent yields by reacting Cu(ClO 4 ) 2 AE 6H 2 O with N,N-bis(2pyridylmethyl)amine (L 1 ); N-(2-pyridylmethyl)-N 0 ,N 0 -dimethylethylenediamine (L 2 ); and N-(2-pyridylmethyl)-N 0 ,N 0 -diethylethylenediamine (L 3 ), respectively, in the presence of slight excess of sodium azide. They are the monomeric Cu(L 1 )(N 3 )(ClO 4 ) (1), the endto-end diazido-bridged Cu 2 (L 2 ) 2 (l-1,3-N 3 ) 2 (ClO 4 ) 2 (2) and the single azido-bridged (l-1,3-) 1D chain [Cu(L 3 )(l-1,3-N 3 )] n (ClO 4 ) n (3). The crystal and molecular structures of these complexes have been solved. The variable temperature magnetic moments of type 2 and type 3 complexes were studied. Temperature dependent susceptibility for 2 was fitted using the Bleaney-Bowers expression which led to the parameters J = À3.43 cm À1 and R = 1 · 10 À5 . The magnetic data for 3 were fitted to BakerÕs expression for S = 1/2 and the parameters obtained were J = 1.6 cm À1 and R = 3.2 · 10 À4 . Crystal data are as follows. Cu(L 1 )(N 3 )(ClO 4 ): Chemical formula, C 12 H 13 ClN 6 O 4 Cu; crystal system, monoclinic; space group, P2 1 /c; a = 8.788 , b = 13.045(15), c = 14.213(15) Å ; b = 102.960(10)°; Z = 4. Cu(L 2 )(l-N 3 )(ClO 4 ): Chemical formula, C 10 H 17 ClN 6 O 4 Cu: crystal system, monoclinic; space group, P2 1 /c; a = 10.790(12), b = 8.568(9), c = 16.651(17) Å ; b = 102.360(10)°; Z = 4. [Cu(L 3 )(l-N 3 )](ClO 4 ): Chemical formula, C 12 H 21 ClN 6 O 4 Cu; crystal system, monoclinic; space group, P2 1 /c; a = 12.331(14), b = 7.804(9), c = 18.64(2) Å ; b = 103.405(10)°; Z = 4.
Dinuclear (V(IV)V(V)) oxophenoxovanadates of general formula [V2O3L] have been synthesized in exc... more Dinuclear (V(IV)V(V)) oxophenoxovanadates of general formula [V2O3L] have been synthesized in excellent yields by reacting bis(acetylacetonato)oxovanadium(IV) with H3L in a 2:1 ratio in acetone under an N2 atmosphere. Here L3- is the deprotonated form of 2,6-bis[{{(2-hydroxybenzyl)(N',N'-(dimethylamino)ethyl)}amino}methyl]-4-methylphenol (H3L1), 2,6-bis[{{(5-methyl-2-hydroxybenzyl)(N',N'-(dimethylamino)ethyl)}amino}methyl]-4-methylphenol (H3L2), 2,6-bis[{{(5-tert-butyl-2-hydroxybenzyl)(N',N'-(dimethylamino)ethyl)}amino}methyl]-4-methylphenol (H3L3), 2,6-bis[{{(5-chloro-2-hydroxybenzyl)(N',N'-(dimethylamino)ethyl)}amino}methyl]-4-methylphenol(H3L4), 2,6-bis[{{(5-bromo-2-hydroxybenzyl)(N'N'-(dimethylamino)ethyl)}amino}methyl]-4-methylphenol (H3L5), or 2,6-bis[{{(5-methoxy-2-hydroxybenzyl)(N'N'-(dimethylamino)ethyl)}methyl]-4-methylphenol (H3L6). In [V2O3L1], both the metal atoms have distorted octahedral geometry. The relative disposition of two terminal V=O groups in the complex is essentially cis. The O=V...V=O torsion angle is 24.6(2) degrees . The V-O(oxo)-V and V-O(phenoxo)-V angles are 117.5(4) and 93.4(3) degrees , respectively. The V...V bond distance is 3.173(5) A. X-ray crystallography, IR, UV-vis, and 1H and 51V NMR measurements show that the mixed-valence complexes contain two indistinguishable vanadium atoms (type III). The thermal ellipsoids of O2, O4, C10, C14, and C15 also suggests a type III complex in the solid state. EPR spectra of solid complexes at 77 K display a single line indicating the localization of the odd electron (3d(xy)1). Valence localization at 77 K is also consistent with the 51V hyperfine structure of the axial EPR spectra (3d(xy)1 ground state) of the complexes in frozen (77 K) dichloromethane solution: S = 1/2, g(parallel) approximately 1.94, g(perpendicular) approximately 1.98, A(parallel) approximately 166 x 10(-4) cm(-1), and A(perpendicular) approximately 68 x 10(-4) cm(-1). In contrast isotropic room-temperature solution spectra of the family have 15 hyperfine lines (g(iso) approximately 1.974 and A(iso) approximately 50 x 10(-4) cm(-1)) revealing that the unpaired electron is delocalized between the metal centers. Crystal data for the [V2O3L1].CH2Cl2 complex are as follows: chemical formula, C32H43O6N4Cl2V2; crystal system, monoclinic; space group, C2/c; a = 18.461(4), b = 17.230(3), c = 13.700(3) A; beta = 117.88(3) degrees ; Z = 8.
The light green coloured complexes of general formula [Re V O(L)Cl(OH 2 )]Cl have been synthesise... more The light green coloured complexes of general formula [Re V O(L)Cl(OH 2 )]Cl have been synthesised in good yields by reacting [Re V O-Cl 3 (AsPh 3 ) 2 ] with HL in dichloromethane in dinitrogen atmosphere. Here, L À is the deprotonated form of N,N-bis(2-pyridylmethyl)amine (HL 1
The pale blue colored complex of the formula [Ni 2 (L)(HL)(l 1,1 -N 3 ) 2 ]ClO 4 (1) has been syn... more The pale blue colored complex of the formula [Ni 2 (L)(HL)(l 1,1 -N 3 ) 2 ]ClO 4 (1) has been synthesised in good yield by the reaction of Ni(ClO 4 ) 2 AE 6H 2 O with N,N-bis(2-methylpyridyl)-3,5-dimethyl-2-hydroxybenzylamine (HL) in methanol in the presence of sodium azide. The crystal structure of the complex has been determined. The X-ray structure reveals that the metal centres are linked by both an end-on bridged azide ligand as well as through an [O-HÁ Á ÁO] interacting unit. Magnetic susceptibility measurements confirm the ferromagnetic character of the complex.
Synthesis, structural characteristics, magnetic studies and DFT calculations in Ni(II) dinuclear ... more Synthesis, structural characteristics, magnetic studies and DFT calculations in Ni(II) dinuclear complexes containing two bridging N 3and an O-H‚‚‚O linkage reveal the existence of ferromagnetic interactions between Ni(II) centers via N 3ligands and antiferromagntic interactions through the H-bonded moiety. The overall magnetic behavior of the system depends on the delicate balance between these two competing interactions.
The synthesis and structural characterisation of a series of cobalt complexes of 1-(anthracen-9-y... more The synthesis and structural characterisation of a series of cobalt complexes of 1-(anthracen-9-ylmethyl)-1,4,8,11-tetraazacyclotetradecane (hereafter L2) is described. The complexes, of the type trans-[CoL2X2]+ in which X=Cl−, NCS− and NO2- were synthesised for their use in photoactivated ligand release studies. X-ray crystal structures show that the macrocycle in all three complexes of the series adopts a trans-(III) configuration. Both thiocyanato ligands
Three kinds of copper(II) azide complexes have been synthesised in excellent yields by reacting C... more Three kinds of copper(II) azide complexes have been synthesised in excellent yields by reacting Cu(ClO 4 ) 2 AE 6H 2 O with N,N-bis(2pyridylmethyl)amine (L 1 ); N-(2-pyridylmethyl)-N 0 ,N 0 -dimethylethylenediamine (L 2 ); and N-(2-pyridylmethyl)-N 0 ,N 0 -diethylethylenediamine (L 3 ), respectively, in the presence of slight excess of sodium azide. They are the monomeric Cu(L 1 )(N 3 )(ClO 4 ) (1), the endto-end diazido-bridged Cu 2 (L 2 ) 2 (l-1,3-N 3 ) 2 (ClO 4 ) 2 (2) and the single azido-bridged (l-1,3-) 1D chain [Cu(L 3 )(l-1,3-N 3 )] n (ClO 4 ) n (3). The crystal and molecular structures of these complexes have been solved. The variable temperature magnetic moments of type 2 and type 3 complexes were studied. Temperature dependent susceptibility for 2 was fitted using the Bleaney-Bowers expression which led to the parameters J = À3.43 cm À1 and R = 1 · 10 À5 . The magnetic data for 3 were fitted to BakerÕs expression for S = 1/2 and the parameters obtained were J = 1.6 cm À1 and R = 3.2 · 10 À4 . Crystal data are as follows. Cu(L 1 )(N 3 )(ClO 4 ): Chemical formula, C 12 H 13 ClN 6 O 4 Cu; crystal system, monoclinic; space group, P2 1 /c; a = 8.788 , b = 13.045(15), c = 14.213(15) Å ; b = 102.960(10)°; Z = 4. Cu(L 2 )(l-N 3 )(ClO 4 ): Chemical formula, C 10 H 17 ClN 6 O 4 Cu: crystal system, monoclinic; space group, P2 1 /c; a = 10.790(12), b = 8.568(9), c = 16.651(17) Å ; b = 102.360(10)°; Z = 4. [Cu(L 3 )(l-N 3 )](ClO 4 ): Chemical formula, C 12 H 21 ClN 6 O 4 Cu; crystal system, monoclinic; space group, P2 1 /c; a = 12.331(14), b = 7.804(9), c = 18.64(2) Å ; b = 103.405(10)°; Z = 4.
Dinuclear (V IV V V ) oxophenoxovanadates of general formula [V 2 O 3 L] have been synthesized in... more Dinuclear (V IV V V ) oxophenoxovanadates of general formula [V 2 O 3 L] have been synthesized in excellent yields by reacting bis(acetylacetonato)oxovanadium(IV) with H 3 L in a 2:1 ratio in acetone under an N 2 atmosphere. Here L 3is the deprotonated form of 2,6-bis [{{(2-hydroxybenzyl)
The light green coloured complexes of general formula [Re V O(L)Cl(OH 2 )]Cl have been synthesise... more The light green coloured complexes of general formula [Re V O(L)Cl(OH 2 )]Cl have been synthesised in good yields by reacting [Re V O-Cl 3 (AsPh 3 ) 2 ] with HL in dichloromethane in dinitrogen atmosphere. Here, L À is the deprotonated form of N,N-bis(2-pyridylmethyl)amine (HL 1
Three kinds of copper(II) azide complexes have been synthesised in excellent yields by reacting C... more Three kinds of copper(II) azide complexes have been synthesised in excellent yields by reacting Cu(ClO 4 ) 2 AE 6H 2 O with N,N-bis(2pyridylmethyl)amine (L 1 ); N-(2-pyridylmethyl)-N 0 ,N 0 -dimethylethylenediamine (L 2 ); and N-(2-pyridylmethyl)-N 0 ,N 0 -diethylethylenediamine (L 3 ), respectively, in the presence of slight excess of sodium azide. They are the monomeric Cu(L 1 )(N 3 )(ClO 4 ) (1), the endto-end diazido-bridged Cu 2 (L 2 ) 2 (l-1,3-N 3 ) 2 (ClO 4 ) 2 (2) and the single azido-bridged (l-1,3-) 1D chain [Cu(L 3 )(l-1,3-N 3 )] n (ClO 4 ) n (3). The crystal and molecular structures of these complexes have been solved. The variable temperature magnetic moments of type 2 and type 3 complexes were studied. Temperature dependent susceptibility for 2 was fitted using the Bleaney-Bowers expression which led to the parameters J = À3.43 cm À1 and R = 1 · 10 À5 . The magnetic data for 3 were fitted to BakerÕs expression for S = 1/2 and the parameters obtained were J = 1.6 cm À1 and R = 3.2 · 10 À4 . Crystal data are as follows. Cu(L 1 )(N 3 )(ClO 4 ): Chemical formula, C 12 H 13 ClN 6 O 4 Cu; crystal system, monoclinic; space group, P2 1 /c; a = 8.788 , b = 13.045(15), c = 14.213(15) Å ; b = 102.960(10)°; Z = 4. Cu(L 2 )(l-N 3 )(ClO 4 ): Chemical formula, C 10 H 17 ClN 6 O 4 Cu: crystal system, monoclinic; space group, P2 1 /c; a = 10.790(12), b = 8.568(9), c = 16.651(17) Å ; b = 102.360(10)°; Z = 4. [Cu(L 3 )(l-N 3 )](ClO 4 ): Chemical formula, C 12 H 21 ClN 6 O 4 Cu; crystal system, monoclinic; space group, P2 1 /c; a = 12.331(14), b = 7.804(9), c = 18.64(2) Å ; b = 103.405(10)°; Z = 4.
Dinuclear (V(IV)V(V)) oxophenoxovanadates of general formula [V2O3L] have been synthesized in exc... more Dinuclear (V(IV)V(V)) oxophenoxovanadates of general formula [V2O3L] have been synthesized in excellent yields by reacting bis(acetylacetonato)oxovanadium(IV) with H3L in a 2:1 ratio in acetone under an N2 atmosphere. Here L3- is the deprotonated form of 2,6-bis[{{(2-hydroxybenzyl)(N',N'-(dimethylamino)ethyl)}amino}methyl]-4-methylphenol (H3L1), 2,6-bis[{{(5-methyl-2-hydroxybenzyl)(N',N'-(dimethylamino)ethyl)}amino}methyl]-4-methylphenol (H3L2), 2,6-bis[{{(5-tert-butyl-2-hydroxybenzyl)(N',N'-(dimethylamino)ethyl)}amino}methyl]-4-methylphenol (H3L3), 2,6-bis[{{(5-chloro-2-hydroxybenzyl)(N',N'-(dimethylamino)ethyl)}amino}methyl]-4-methylphenol(H3L4), 2,6-bis[{{(5-bromo-2-hydroxybenzyl)(N'N'-(dimethylamino)ethyl)}amino}methyl]-4-methylphenol (H3L5), or 2,6-bis[{{(5-methoxy-2-hydroxybenzyl)(N'N'-(dimethylamino)ethyl)}methyl]-4-methylphenol (H3L6). In [V2O3L1], both the metal atoms have distorted octahedral geometry. The relative disposition of two terminal V=O groups in the complex is essentially cis. The O=V...V=O torsion angle is 24.6(2) degrees . The V-O(oxo)-V and V-O(phenoxo)-V angles are 117.5(4) and 93.4(3) degrees , respectively. The V...V bond distance is 3.173(5) A. X-ray crystallography, IR, UV-vis, and 1H and 51V NMR measurements show that the mixed-valence complexes contain two indistinguishable vanadium atoms (type III). The thermal ellipsoids of O2, O4, C10, C14, and C15 also suggests a type III complex in the solid state. EPR spectra of solid complexes at 77 K display a single line indicating the localization of the odd electron (3d(xy)1). Valence localization at 77 K is also consistent with the 51V hyperfine structure of the axial EPR spectra (3d(xy)1 ground state) of the complexes in frozen (77 K) dichloromethane solution: S = 1/2, g(parallel) approximately 1.94, g(perpendicular) approximately 1.98, A(parallel) approximately 166 x 10(-4) cm(-1), and A(perpendicular) approximately 68 x 10(-4) cm(-1). In contrast isotropic room-temperature solution spectra of the family have 15 hyperfine lines (g(iso) approximately 1.974 and A(iso) approximately 50 x 10(-4) cm(-1)) revealing that the unpaired electron is delocalized between the metal centers. Crystal data for the [V2O3L1].CH2Cl2 complex are as follows: chemical formula, C32H43O6N4Cl2V2; crystal system, monoclinic; space group, C2/c; a = 18.461(4), b = 17.230(3), c = 13.700(3) A; beta = 117.88(3) degrees ; Z = 8.
The pale blue colored complex of the formula [Ni 2 (L)(HL)(l 1,1 -N 3 ) 2 ]ClO 4 (1) has been syn... more The pale blue colored complex of the formula [Ni 2 (L)(HL)(l 1,1 -N 3 ) 2 ]ClO 4 (1) has been synthesised in good yield by the reaction of Ni(ClO 4 ) 2 AE 6H 2 O with N,N-bis(2-methylpyridyl)-3,5-dimethyl-2-hydroxybenzylamine (HL) in methanol in the presence of sodium azide. The crystal structure of the complex has been determined. The X-ray structure reveals that the metal centres are linked by both an end-on bridged azide ligand as well as through an [O-HÁ Á ÁO] interacting unit. Magnetic susceptibility measurements confirm the ferromagnetic character of the complex.
The light green coloured complexes of general formula [Re V O(L)Cl(OH 2 )]Cl have been synthesise... more The light green coloured complexes of general formula [Re V O(L)Cl(OH 2 )]Cl have been synthesised in good yields by reacting [Re V O-Cl 3 (AsPh 3 ) 2 ] with HL in dichloromethane in dinitrogen atmosphere. Here, L À is the deprotonated form of N,N-bis(2-pyridylmethyl)amine (HL 1
Three kinds of copper(II) azide complexes have been synthesised in excellent yields by reacting C... more Three kinds of copper(II) azide complexes have been synthesised in excellent yields by reacting Cu(ClO 4 ) 2 AE 6H 2 O with N,N-bis(2pyridylmethyl)amine (L 1 ); N-(2-pyridylmethyl)-N 0 ,N 0 -dimethylethylenediamine (L 2 ); and N-(2-pyridylmethyl)-N 0 ,N 0 -diethylethylenediamine (L 3 ), respectively, in the presence of slight excess of sodium azide. They are the monomeric Cu(L 1 )(N 3 )(ClO 4 ) (1), the endto-end diazido-bridged Cu 2 (L 2 ) 2 (l-1,3-N 3 ) 2 (ClO 4 ) 2 (2) and the single azido-bridged (l-1,3-) 1D chain [Cu(L 3 )(l-1,3-N 3 )] n (ClO 4 ) n (3). The crystal and molecular structures of these complexes have been solved. The variable temperature magnetic moments of type 2 and type 3 complexes were studied. Temperature dependent susceptibility for 2 was fitted using the Bleaney-Bowers expression which led to the parameters J = À3.43 cm À1 and R = 1 · 10 À5 . The magnetic data for 3 were fitted to BakerÕs expression for S = 1/2 and the parameters obtained were J = 1.6 cm À1 and R = 3.2 · 10 À4 . Crystal data are as follows. Cu(L 1 )(N 3 )(ClO 4 ): Chemical formula, C 12 H 13 ClN 6 O 4 Cu; crystal system, monoclinic; space group, P2 1 /c; a = 8.788 , b = 13.045(15), c = 14.213(15) Å ; b = 102.960(10)°; Z = 4. Cu(L 2 )(l-N 3 )(ClO 4 ): Chemical formula, C 10 H 17 ClN 6 O 4 Cu: crystal system, monoclinic; space group, P2 1 /c; a = 10.790(12), b = 8.568(9), c = 16.651(17) Å ; b = 102.360(10)°; Z = 4. [Cu(L 3 )(l-N 3 )](ClO 4 ): Chemical formula, C 12 H 21 ClN 6 O 4 Cu; crystal system, monoclinic; space group, P2 1 /c; a = 12.331(14), b = 7.804(9), c = 18.64(2) Å ; b = 103.405(10)°; Z = 4.
Dinuclear (V(IV)V(V)) oxophenoxovanadates of general formula [V2O3L] have been synthesized in exc... more Dinuclear (V(IV)V(V)) oxophenoxovanadates of general formula [V2O3L] have been synthesized in excellent yields by reacting bis(acetylacetonato)oxovanadium(IV) with H3L in a 2:1 ratio in acetone under an N2 atmosphere. Here L3- is the deprotonated form of 2,6-bis[{{(2-hydroxybenzyl)(N',N'-(dimethylamino)ethyl)}amino}methyl]-4-methylphenol (H3L1), 2,6-bis[{{(5-methyl-2-hydroxybenzyl)(N',N'-(dimethylamino)ethyl)}amino}methyl]-4-methylphenol (H3L2), 2,6-bis[{{(5-tert-butyl-2-hydroxybenzyl)(N',N'-(dimethylamino)ethyl)}amino}methyl]-4-methylphenol (H3L3), 2,6-bis[{{(5-chloro-2-hydroxybenzyl)(N',N'-(dimethylamino)ethyl)}amino}methyl]-4-methylphenol(H3L4), 2,6-bis[{{(5-bromo-2-hydroxybenzyl)(N'N'-(dimethylamino)ethyl)}amino}methyl]-4-methylphenol (H3L5), or 2,6-bis[{{(5-methoxy-2-hydroxybenzyl)(N'N'-(dimethylamino)ethyl)}methyl]-4-methylphenol (H3L6). In [V2O3L1], both the metal atoms have distorted octahedral geometry. The relative disposition of two terminal V=O groups in the complex is essentially cis. The O=V...V=O torsion angle is 24.6(2) degrees . The V-O(oxo)-V and V-O(phenoxo)-V angles are 117.5(4) and 93.4(3) degrees , respectively. The V...V bond distance is 3.173(5) A. X-ray crystallography, IR, UV-vis, and 1H and 51V NMR measurements show that the mixed-valence complexes contain two indistinguishable vanadium atoms (type III). The thermal ellipsoids of O2, O4, C10, C14, and C15 also suggests a type III complex in the solid state. EPR spectra of solid complexes at 77 K display a single line indicating the localization of the odd electron (3d(xy)1). Valence localization at 77 K is also consistent with the 51V hyperfine structure of the axial EPR spectra (3d(xy)1 ground state) of the complexes in frozen (77 K) dichloromethane solution: S = 1/2, g(parallel) approximately 1.94, g(perpendicular) approximately 1.98, A(parallel) approximately 166 x 10(-4) cm(-1), and A(perpendicular) approximately 68 x 10(-4) cm(-1). In contrast isotropic room-temperature solution spectra of the family have 15 hyperfine lines (g(iso) approximately 1.974 and A(iso) approximately 50 x 10(-4) cm(-1)) revealing that the unpaired electron is delocalized between the metal centers. Crystal data for the [V2O3L1].CH2Cl2 complex are as follows: chemical formula, C32H43O6N4Cl2V2; crystal system, monoclinic; space group, C2/c; a = 18.461(4), b = 17.230(3), c = 13.700(3) A; beta = 117.88(3) degrees ; Z = 8.
The light green coloured complexes of general formula [Re V O(L)Cl(OH 2 )]Cl have been synthesise... more The light green coloured complexes of general formula [Re V O(L)Cl(OH 2 )]Cl have been synthesised in good yields by reacting [Re V O-Cl 3 (AsPh 3 ) 2 ] with HL in dichloromethane in dinitrogen atmosphere. Here, L À is the deprotonated form of N,N-bis(2-pyridylmethyl)amine (HL 1
The pale blue colored complex of the formula [Ni 2 (L)(HL)(l 1,1 -N 3 ) 2 ]ClO 4 (1) has been syn... more The pale blue colored complex of the formula [Ni 2 (L)(HL)(l 1,1 -N 3 ) 2 ]ClO 4 (1) has been synthesised in good yield by the reaction of Ni(ClO 4 ) 2 AE 6H 2 O with N,N-bis(2-methylpyridyl)-3,5-dimethyl-2-hydroxybenzylamine (HL) in methanol in the presence of sodium azide. The crystal structure of the complex has been determined. The X-ray structure reveals that the metal centres are linked by both an end-on bridged azide ligand as well as through an [O-HÁ Á ÁO] interacting unit. Magnetic susceptibility measurements confirm the ferromagnetic character of the complex.
Synthesis, structural characteristics, magnetic studies and DFT calculations in Ni(II) dinuclear ... more Synthesis, structural characteristics, magnetic studies and DFT calculations in Ni(II) dinuclear complexes containing two bridging N 3and an O-H‚‚‚O linkage reveal the existence of ferromagnetic interactions between Ni(II) centers via N 3ligands and antiferromagntic interactions through the H-bonded moiety. The overall magnetic behavior of the system depends on the delicate balance between these two competing interactions.
The synthesis and structural characterisation of a series of cobalt complexes of 1-(anthracen-9-y... more The synthesis and structural characterisation of a series of cobalt complexes of 1-(anthracen-9-ylmethyl)-1,4,8,11-tetraazacyclotetradecane (hereafter L2) is described. The complexes, of the type trans-[CoL2X2]+ in which X=Cl−, NCS− and NO2- were synthesised for their use in photoactivated ligand release studies. X-ray crystal structures show that the macrocycle in all three complexes of the series adopts a trans-(III) configuration. Both thiocyanato ligands
Three kinds of copper(II) azide complexes have been synthesised in excellent yields by reacting C... more Three kinds of copper(II) azide complexes have been synthesised in excellent yields by reacting Cu(ClO 4 ) 2 AE 6H 2 O with N,N-bis(2pyridylmethyl)amine (L 1 ); N-(2-pyridylmethyl)-N 0 ,N 0 -dimethylethylenediamine (L 2 ); and N-(2-pyridylmethyl)-N 0 ,N 0 -diethylethylenediamine (L 3 ), respectively, in the presence of slight excess of sodium azide. They are the monomeric Cu(L 1 )(N 3 )(ClO 4 ) (1), the endto-end diazido-bridged Cu 2 (L 2 ) 2 (l-1,3-N 3 ) 2 (ClO 4 ) 2 (2) and the single azido-bridged (l-1,3-) 1D chain [Cu(L 3 )(l-1,3-N 3 )] n (ClO 4 ) n (3). The crystal and molecular structures of these complexes have been solved. The variable temperature magnetic moments of type 2 and type 3 complexes were studied. Temperature dependent susceptibility for 2 was fitted using the Bleaney-Bowers expression which led to the parameters J = À3.43 cm À1 and R = 1 · 10 À5 . The magnetic data for 3 were fitted to BakerÕs expression for S = 1/2 and the parameters obtained were J = 1.6 cm À1 and R = 3.2 · 10 À4 . Crystal data are as follows. Cu(L 1 )(N 3 )(ClO 4 ): Chemical formula, C 12 H 13 ClN 6 O 4 Cu; crystal system, monoclinic; space group, P2 1 /c; a = 8.788 , b = 13.045(15), c = 14.213(15) Å ; b = 102.960(10)°; Z = 4. Cu(L 2 )(l-N 3 )(ClO 4 ): Chemical formula, C 10 H 17 ClN 6 O 4 Cu: crystal system, monoclinic; space group, P2 1 /c; a = 10.790(12), b = 8.568(9), c = 16.651(17) Å ; b = 102.360(10)°; Z = 4. [Cu(L 3 )(l-N 3 )](ClO 4 ): Chemical formula, C 12 H 21 ClN 6 O 4 Cu; crystal system, monoclinic; space group, P2 1 /c; a = 12.331(14), b = 7.804(9), c = 18.64(2) Å ; b = 103.405(10)°; Z = 4.
Dinuclear (V IV V V ) oxophenoxovanadates of general formula [V 2 O 3 L] have been synthesized in... more Dinuclear (V IV V V ) oxophenoxovanadates of general formula [V 2 O 3 L] have been synthesized in excellent yields by reacting bis(acetylacetonato)oxovanadium(IV) with H 3 L in a 2:1 ratio in acetone under an N 2 atmosphere. Here L 3is the deprotonated form of 2,6-bis [{{(2-hydroxybenzyl)
The light green coloured complexes of general formula [Re V O(L)Cl(OH 2 )]Cl have been synthesise... more The light green coloured complexes of general formula [Re V O(L)Cl(OH 2 )]Cl have been synthesised in good yields by reacting [Re V O-Cl 3 (AsPh 3 ) 2 ] with HL in dichloromethane in dinitrogen atmosphere. Here, L À is the deprotonated form of N,N-bis(2-pyridylmethyl)amine (HL 1
Three kinds of copper(II) azide complexes have been synthesised in excellent yields by reacting C... more Three kinds of copper(II) azide complexes have been synthesised in excellent yields by reacting Cu(ClO 4 ) 2 AE 6H 2 O with N,N-bis(2pyridylmethyl)amine (L 1 ); N-(2-pyridylmethyl)-N 0 ,N 0 -dimethylethylenediamine (L 2 ); and N-(2-pyridylmethyl)-N 0 ,N 0 -diethylethylenediamine (L 3 ), respectively, in the presence of slight excess of sodium azide. They are the monomeric Cu(L 1 )(N 3 )(ClO 4 ) (1), the endto-end diazido-bridged Cu 2 (L 2 ) 2 (l-1,3-N 3 ) 2 (ClO 4 ) 2 (2) and the single azido-bridged (l-1,3-) 1D chain [Cu(L 3 )(l-1,3-N 3 )] n (ClO 4 ) n (3). The crystal and molecular structures of these complexes have been solved. The variable temperature magnetic moments of type 2 and type 3 complexes were studied. Temperature dependent susceptibility for 2 was fitted using the Bleaney-Bowers expression which led to the parameters J = À3.43 cm À1 and R = 1 · 10 À5 . The magnetic data for 3 were fitted to BakerÕs expression for S = 1/2 and the parameters obtained were J = 1.6 cm À1 and R = 3.2 · 10 À4 . Crystal data are as follows. Cu(L 1 )(N 3 )(ClO 4 ): Chemical formula, C 12 H 13 ClN 6 O 4 Cu; crystal system, monoclinic; space group, P2 1 /c; a = 8.788 , b = 13.045(15), c = 14.213(15) Å ; b = 102.960(10)°; Z = 4. Cu(L 2 )(l-N 3 )(ClO 4 ): Chemical formula, C 10 H 17 ClN 6 O 4 Cu: crystal system, monoclinic; space group, P2 1 /c; a = 10.790(12), b = 8.568(9), c = 16.651(17) Å ; b = 102.360(10)°; Z = 4. [Cu(L 3 )(l-N 3 )](ClO 4 ): Chemical formula, C 12 H 21 ClN 6 O 4 Cu; crystal system, monoclinic; space group, P2 1 /c; a = 12.331(14), b = 7.804(9), c = 18.64(2) Å ; b = 103.405(10)°; Z = 4.
Dinuclear (V(IV)V(V)) oxophenoxovanadates of general formula [V2O3L] have been synthesized in exc... more Dinuclear (V(IV)V(V)) oxophenoxovanadates of general formula [V2O3L] have been synthesized in excellent yields by reacting bis(acetylacetonato)oxovanadium(IV) with H3L in a 2:1 ratio in acetone under an N2 atmosphere. Here L3- is the deprotonated form of 2,6-bis[{{(2-hydroxybenzyl)(N',N'-(dimethylamino)ethyl)}amino}methyl]-4-methylphenol (H3L1), 2,6-bis[{{(5-methyl-2-hydroxybenzyl)(N',N'-(dimethylamino)ethyl)}amino}methyl]-4-methylphenol (H3L2), 2,6-bis[{{(5-tert-butyl-2-hydroxybenzyl)(N',N'-(dimethylamino)ethyl)}amino}methyl]-4-methylphenol (H3L3), 2,6-bis[{{(5-chloro-2-hydroxybenzyl)(N',N'-(dimethylamino)ethyl)}amino}methyl]-4-methylphenol(H3L4), 2,6-bis[{{(5-bromo-2-hydroxybenzyl)(N'N'-(dimethylamino)ethyl)}amino}methyl]-4-methylphenol (H3L5), or 2,6-bis[{{(5-methoxy-2-hydroxybenzyl)(N'N'-(dimethylamino)ethyl)}methyl]-4-methylphenol (H3L6). In [V2O3L1], both the metal atoms have distorted octahedral geometry. The relative disposition of two terminal V=O groups in the complex is essentially cis. The O=V...V=O torsion angle is 24.6(2) degrees . The V-O(oxo)-V and V-O(phenoxo)-V angles are 117.5(4) and 93.4(3) degrees , respectively. The V...V bond distance is 3.173(5) A. X-ray crystallography, IR, UV-vis, and 1H and 51V NMR measurements show that the mixed-valence complexes contain two indistinguishable vanadium atoms (type III). The thermal ellipsoids of O2, O4, C10, C14, and C15 also suggests a type III complex in the solid state. EPR spectra of solid complexes at 77 K display a single line indicating the localization of the odd electron (3d(xy)1). Valence localization at 77 K is also consistent with the 51V hyperfine structure of the axial EPR spectra (3d(xy)1 ground state) of the complexes in frozen (77 K) dichloromethane solution: S = 1/2, g(parallel) approximately 1.94, g(perpendicular) approximately 1.98, A(parallel) approximately 166 x 10(-4) cm(-1), and A(perpendicular) approximately 68 x 10(-4) cm(-1). In contrast isotropic room-temperature solution spectra of the family have 15 hyperfine lines (g(iso) approximately 1.974 and A(iso) approximately 50 x 10(-4) cm(-1)) revealing that the unpaired electron is delocalized between the metal centers. Crystal data for the [V2O3L1].CH2Cl2 complex are as follows: chemical formula, C32H43O6N4Cl2V2; crystal system, monoclinic; space group, C2/c; a = 18.461(4), b = 17.230(3), c = 13.700(3) A; beta = 117.88(3) degrees ; Z = 8.
The pale blue colored complex of the formula [Ni 2 (L)(HL)(l 1,1 -N 3 ) 2 ]ClO 4 (1) has been syn... more The pale blue colored complex of the formula [Ni 2 (L)(HL)(l 1,1 -N 3 ) 2 ]ClO 4 (1) has been synthesised in good yield by the reaction of Ni(ClO 4 ) 2 AE 6H 2 O with N,N-bis(2-methylpyridyl)-3,5-dimethyl-2-hydroxybenzylamine (HL) in methanol in the presence of sodium azide. The crystal structure of the complex has been determined. The X-ray structure reveals that the metal centres are linked by both an end-on bridged azide ligand as well as through an [O-HÁ Á ÁO] interacting unit. Magnetic susceptibility measurements confirm the ferromagnetic character of the complex.
The light green coloured complexes of general formula [Re V O(L)Cl(OH 2 )]Cl have been synthesise... more The light green coloured complexes of general formula [Re V O(L)Cl(OH 2 )]Cl have been synthesised in good yields by reacting [Re V O-Cl 3 (AsPh 3 ) 2 ] with HL in dichloromethane in dinitrogen atmosphere. Here, L À is the deprotonated form of N,N-bis(2-pyridylmethyl)amine (HL 1
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