الفهرس 
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Abstract
In this work a series of sulphonamide imine ligands (HL1-5) were prepared by the condensation of the triple sulpha drugs namely (Sulfamethazine, Sulfamerazine and Sulfadiazine) with salicylaldehyde and 2-hydroxy1-naphthaldehyde.
Direct reactions with copper acetate dihydrate and zinc acetate dihydrate furnished the corresponding complexes in good yields. The structures of the ligands and their metal complexes were fully characterized using elemental analysis, molar conductance, spectroscopic measurements (FT-IR, UV-vis, 1HNMR, Fluorescence, EPR and mass spectra), magnetic susceptibility and thermal studies.
The mass spectra for the sulphonamide imine ligands HL1-5 are in accordance with the ions produced under the electron impact spectroscopy. The fragmentation pattern of HL1,2 are similar but differ from those of HL3-5.
The 1HNMR spectra of the sulphonamide imine ligands HL1-5 as d6-DMSO solutions were carried out and exhibit a doublet signal in the range of δ 8.98-9.64 ppm assignable to the azomethine proton (-CH=N, 1H) and displayed a signal characteristic of (OH-) proton in the range of δ 9.64-12.58 ppm that disappeared in presence of D2O. However a signal observed at the range of δ 5.91-5.97 ppm which assigned to sulphonamide proton (-SO2-NH-). Methyl group(s) of the pyrimidine ring of the free ligand HL1-4 can be detected in the range δ 2.24-2.32 ppm and disappeared in the spectra of HL5 free ligand.
The FT-IR spectra of the sulphonamide imine ligands HL1-5 displayed band in the range 1570-1595 cm-1 assignable to ʋ(C=N)azomethine ,band in the range from 3393-3461 cm-1 due to ν(OH) and ν(NH) , band in the range 1310-1340 cm-1 and 1149-1160 cm-1 assigned to ν(SO2)asym and ν(SO2)sym ,respectively and band in the range 1238-1261 cm-1 which characteristic for ν(C-O)phenolic .
The electronic spectra of the sulphonamide imine ligands HL1-5 displayed high intense bands at 260 – 270, 320 – 355 and 415 – 475nm. These bands could be assigned to the intraligand π- π*, n- π* and charge transfer transitions tend to take place within the organic molecule, respectively.
As judged by scanning electron microscopy (SEM), nanosized ligands HL1-5were obtained as well-separated spherical nanoparticles with some interconnection degree. Nanosized suphonamide imine ligands prepared from sulphamerazine drug exhibited the smaller diameter.
In all complexes, the data revealed the formation of non-electrolytic mononuclear complex species as their molar conductance ranged from 2-4 Ω−1mol−1cm2.
The FT-IR spectra of the Cu(II) and Zn(II) complexes of the sulphonamide imine ligands displayed band at 1512-1569 cm-1 due to ν (C=N)azomethine , band in the range of 1520-1554 cm-1 due to ν (C=N)Pyrimidine , band in the range 1252-1285 cm-1 characteristic of ν (C-O)phenolic . The coordination of the metal ion to the phenolic oxygen (C-O) of all metal (II) complexes was confirmed by presence upward shifted (Δν=15-24 cm-1) compared to that of the organic ligands, whilst the FT-IR spectra of the [Zn(HL22)(OAc)2] and [Zn(HL3,4)(OAc)2].2H2O didn`t give a noticeable shift for (C-O)phenolic from that of the organic ligands confirming (C-O) bond didn`t participates in the coordination ion. The bidentate and mondentate nature of the acetato group was confirmed by the appearance shift Δν ˂ 200 cm-1 and Δν˃200 cm-1, respectively. The FT-IR spectra of the hydrated complexes display a broad medium band at 3200-3500, cm-1, assigned to ν(OH) of the water of crystallization and ν(NH) of the sulphonamide moiety. All the spectra of the complexes display bands at 425-462 and 500 - 586 cm-1 characteristic of the ν (M-O) and ν(M-N), respectively.
All copper(II) complexes have room temperature effective magnetic moment μeff of 1.90-2.5 B.M characteristic of magnetically diluted d9 species, while the room temperature magnetic moment value of zero for all zinc(II) complexes is consistent with the property of d10 configuration.
The electronic spectra of [Cu L2-5(OAc)].nH2O, n = 0 -3, exhibit a broad band at 690 – 700 nm which is consistent with that reported for square planar copper(II) complexes with bidentate ligands. Whilst The electronic spectrum of [L1Cu(OAc)] exhibits only one broad band at 765 nm, in agreement with the data reported for tetragonally distorted or trigonal bipyramidal copper(II) complexes.
The electronic spectra of all zinc(II) complexes did not exhibit d-d transitional bands which is expected for the completely filled d-orbitals configuration, Based on the elemental analyses, FT-IR, UV-vis, and 1HNMR, spectral data , four coordinate probably with tetrahedral zinc(II) complexes could be assumed.
The fluorescence properties of the examined ligands displayed photoluminescence originating from intraligand (π–π*) transitions. Metal-mediated enhancement is observed on complexation of all the prepared ligands with Zn(II) ,whereas metal-mediated fluorescence quenching occurs in Cu(II) complexes. Meanwhile, this preliminary study of the fluorescence properties of the prepared sulphonamide imine ligands and their copper and zinc complexes suggested that these liagnds are promising candidates for dual-function fluorescent chemosensors for zinc and copper cations.
The room temperature EPR spectra of the polycrystalline [Cu(L1-3)(OAc)] and [Cu(L4)(OAc)].3H2O display resonances characteristic of square planner while the tetrahaydral geometrical structure is assumed for [Cu(L5)(OAc)].2H2O.
The 1H-NMR spectra of the zinc (II) complexes exhibit a signal at δ 8.60-10.05 ppm assigned to the azomethine (-CH=N, 1H) proton, The higher chemical shift of this signal by (Δδ = +0.27 – +1.07) in all zinc (II) complexes could be taken as an evidence for the participation of the azomethine nitrogen in bonding to the zinc(II) ion. The spectra of [Zn(HL22)(OAc)2], [Zn(HL3)(OAc)2].2H2O and [Zn(HL4)(OAc)2].2H2O exhibit signal at δ 12.65, 9.65, 9.65 ppm ,respectively, characteristic to (OH, 1H), which is absent in the spectra of [Zn(L12)].2H2O and [Zn(L52)] confirming its deprotonation of the phenolic (-OH) in the latter two complexes. The existence of the acetato group as coordinated species is proved from the existence of a signal at δ 3.30, 3.44 and 3.49 ppm each with integration corresponding to 6H for [Zn(HL22)(OAc)2],[Zn(HL3)(OAc)2].2H2O and [Zn(HL4)(OAc)2].2H2O, respectively. In addition the methyl group can be detected by the signal at δ2.40 ppm with integration corresponding to 3H for all zinc (II) complexes, except the [Zn(L52)], is characteristic of the pyrimidine methyl protons. The1H-NMR spectra of all zinc(II) complexes display a signal at δ 5.96 ppm with.