بسم الله الرحمن الرحيم ربِ اشرَح لي صَدري * وَيَسِر ليِ أمري * واحلُل عُقدةً مِن لِسانيِ * يَفقَهوا قَولِي* *صدق الله العظيم* سورة طه الآية (24)
Transition Metal Complexes of Some Hydrazones Containing Sulfur Compounds: Synthesis and Application Studies. by Omima Mohamed Ibrahim Adly
Outlines 1-Introduction a) General Background b) Aim of the work. 2-Experimental Preparation of S-methyldithiocarbazate. Synthesis of the organic ligands Synthesis of the metal complexes
3 - Results and Discussion Part I) The organic ligands Part II) The metal complexes Part III) Thermodynamicparameters Part VI) Biological studies 4- Conclusion
a) General Background • Organic compounds containing oxygen, nitrogen and/or sulfur as coordinating sites gave rich and valuable knowledge in coordination chemistry. • Organic sulfur as ligands were increased due to their important effects in the biological mechanisms in the living organisms. • S-methyldithiocarbazate and its derivatives and their metal complexes are considered important examples of the organic sulfur ligands that have significant biological activities, such as: antifungal, antimicrobial, antiviral, antimalarial, antioxidant, anticancer and antitumar
S-methyldithiocarbazate (SMDTC) is the sulfur analogues of methylcarbamate Condensation of SMDTC with aldehydes and ketones gave the corresponding hydrazone ligands
Aim of the work • Synthesis of SMDTC- hydrazones by reacting SMDTC with different aldehydes and ketones. • Synthesis of transition metal complexes of the synthesized ligands. • Elucidation of the geometrical structures of the synthesized compounds. • Study the thermal stability and thermodynamic parameters of the prepared solid complexes. • Study the biological activity of the new synthesized ligands and their metal complexes.
Experimental Preparation of S-methyldithiocarbazate
Reflux Methanol 2 h Synthesis of Hydrazone Metal Complexes H2La H2Lb H3Lc H2Ld M2+ or M3+ Complexes + M2+ = Cu(II), Ni(II), Co(II), Zn(II), Cd(II) or VO(IV) M3+ = Fe(III) or Cr(III)
The used techniques are: • Elemental (C, H, N and S) analyses. • Metal ions analyses using EDTA • 1H-NMR spectra • Mass spectra • Infrared spectra • Electronic spectra • ESR spectra • Magnetic measurements • Molar conductance measurements • Thermal gravimetric analysis (TGA) • Melting points
Part I: The ligands (A) Physical and analytical data of the hydrazone, H2La, H2Lb, H3Lc and H2Ld ligands
B) Infrared Spectra Infrared spectra of (A) H2La ligand, (B) SMDTC and (C) Salicylaldehyde
C) MassSpectra Mass spectrum of the hydrazone, H2La, ligand.
D) 1H NMR Spectra 1H-NMR spectrum for the hydrazone H2La ligand
(E) Acid dissociationconstant The potentiometric titration curves of H2La, H2Lb and H3Lc
(F) Distribution of the dissociated species of the hydrazone ligands The distribution curves of the dissociated ligand species as a function of pH show that αo, α1andα2 change monotonically with pH.
(G) Molecular Orbital Calculations H2La H2Lb H3Lc H2Ld
Structural parameters data of the ligands as calculated by the Hyperchem 7.5 program
Physical and analytical data for hydrazone, H2La, ligand and its transition metal complexes
Physical and analytical data for hydrazone, H2Lb, ligand and its transition metal complexes
Physical and analytical data for hydrazone, H3Lc, ligand and its transition metal complexes
Physical and analytical data for hydrazone, H2Ld, ligand and its transition metal complexes
B) Infrared spectra • Most complexes have a broad band which attributed to (OH) group. • Disappearance NH band of the free ligands for all complexes. • Azomethine (C=N) of the free ligands shifted to lower frequencies. This shift is due to the complexation. • Disappearance of the band assigned to (C=S) of the free ligand and appearing of a new band (C-S) in their metal complexes. • The appearance of new band assigned to ν(M-O) and (M-N).
Characteristic IR frequencies (cm-1) for H2Lb, ligand and its transition metal complexes.
C) Electronic spectra, magnetic and Condactance measurements (i) Cu(II) Complexes Electronic absorption bands, magnetic moments and molar conductance of Cu(II) complexes 1, 8, 14 and 21.
Cu(II) Complexes Structures of the square planar Cu(II) complexes 1, 8, 14 and 21.
ESR spectra [CuLd]2.2H2O (21) [Cu(HLc)]2 (14) X-Band ESR spectra of (a) [Cu(HLc)]2 (14) and (b) [CuLd]2.2H2O (21) complexes
(ii) Ni(II) Complexes Electronic absorption bands, magnetic moments molar conductance of Ni(II) complexes 2, 9, 15 and 22.
Ni(II) Complexes Structures of the Ni(II) complexes 2, 9, 15 and 22.
(iii) Co(II) Complexes Electronic absorption bands, magnetic moments and molar conductance of Co(II) complexes 3, 16 and 23
Co(II) Complexes Structures of the octahedral Co(II) complexes 3, 16 and 23.
TGA analysis TGA-DrTGA of [CoLd(H2O)2]2.H2O (23)
iv) VO(IV) Complexes Electronic absorption bands, magnetic moments and molar conductance of VO(IV) complexes 4, 10, 17 and 24.
VO(IV) Complexes Structures of the VO(IV) complexes 4, 10, 17 and 24.
ESR spectra [VOLd(H2O)]2.2H2O (24) [VO(HLc)]2 (17) X-Band ESR spectra of (a) [VO(HLc)]2 (17) and (b) [VOLd(H2O)]2.2H2O (24)
v) Fe(III) Complexes Electronic absorption bands, magnetic moments and molar conductance of Fe(III) complexes 5, 11 and 18.
Fe(III) Complexes Structures of the octahedral Fe(III) complexes 5, 11 and 18
TGA analysis TGA-DrTGA of [FeLa(MeOH)2]2.(NO3)2.H2O (5)