Synthesis and Characterization of new Manganese(II), Cobalt(II), Cadmium(II) and Mercury(II) Complexes with ligand [N-(3-acetylphenylcarbamothioyl)-2-chloroacetamide] and their Antibacterial Studies

Addition chloro acetyl isothiocyanate (C3H2ClNOS) with 3-Aminoaceto phenone (C8H9NO) to prepare a fresh Ligand [N-(3-acetyl phenyl carbamothioyl)-2-chloroacetamide](L). The ligand (L) behaves as bidentate coordinating through O and S donor with metal ions, the general formula of all complexes [M(L)2(Cl)2](M+2 = Manganese(II), Cobalt(II), Cadmium(II) and Mercury(II)). Compounds were investigation by Proton-1, Carbon -13 NMR spectra (ligand (L) only), Element Microanalysis for C, N, H, O, S, Fourier-transform infrared, UV visible, Conductance, Magnetic susceptibility and Atomic Absorption (A.A). Based on spectral data, complexes appear octahedral geometry. The anti-bacterial activity of the complexes against two type of bacterial was higher than for free ligand.


1.Introduction
3-Aminoacetophenone is one of the most typical aromatic carbonyls which show a wide diversity and an important category of ligands in. chemistry coordination chemistry and the creation of large applications in various fields, such as bio chemistry, nonorganic chemistry and analytical chemistry. Several biological important acetophenone derivatives have been reported in peppers possess, antihuman immunodeficiency virus, antibacterial, antifungal, anti-inflammatory antitumor and antimicrobial [1,2] .Complexes of transition metals were used in different industries such as electro plating, leather tanning ,chemical industry, metal finishing, and others Thus these metals enter in water supply through industrial waste [3].The implication of metal chelation is carried in many important biological processes, where the coordination occurs between different metal ions and a broad range of ligands. As the transition metal complexes contribute a diverse and rich field of research, these complexes received much attention because of their applications in biology, medicine and industry [4]. complexes of Schiff bases and Schiff bases which prepared from reaction primary amines and acetophenone derivatives, have been used as bioreactors to open the door for important research to be consider among chemists to record important factors in solving the recent problems in the living [5].The ligand type [HL], has been prepared from Isatin and 3-aminoacetophenone in the presence of KOH. This ligand has been used to prepare Nickek( ) and Cobalt( ) complexes in the ratio of (1:1) metal-ligand. All compounds have been characterized by spectroscopic methods FTIR ,UV-Vis, C.H.N, thin-layer chromatography, mass spectrum, X-ray diffraction, magnetic moment, conductivity measurements and milting point [6].Chain of new complexes of Copper( ), Nickel( ) and Zink( ) are synthesized from the schiff base ligand derived from 2-amino benzaldehyde with 3-amino acetophenone and investigated by elemental analyzer, cyclic voltammetry(CV), conductivity, and spectroscopic methods.(UV-Vis, IR, NMR and MS) biological efficient of the ligand and its complexes has been studies against various types of bacterial [7]. Synthesis Cobalt( ), Nickel( ) and Copper( ) complexes with ligand Schiff base the reaction between the new derived from Salicylaldehyde, 3-amino acetophenone The compounds were investigation by UV-vis, FT-IR, 1 H-NMR spectroscopes, magnetic susceptibility and molar conductivity [8].The purpose of this work is to synthesis and identification a new ligand [N-(3-acetylphenyl carbamothioyl)-2chloroacetamide](L),and it's Manganese( ), Cobalt( ),Cadmium( ) and Mercury( ) metal complexes.

Materials and reagents
All solvents, reagents, chemical and metal chloride salts from BDH, Merck and Fluka com.are commercially available and used as received without purification.

Physical measurements.
1 Hand 13 C-NMR spectra were registered by using Ultra Shield 300 MH z Switzerland at University of Al al-Bayt, Jordan. Melting point was recorded by using Stuart melting point apparatus. FT-IR spectra have been registered at (4000-400) cm -1 range and(4000-200)cmrange of ligand and metal complexes on a Shimadzu IR-470 spectrum used KBr and CsI pellets. UV-160 Shimadzu spectrophotometer at 25 C for 10 -3 M solution DMSO with 1.000 ± 0.001 cm matched quartz cell was used to obtain. electronic spectra Philips PW. Digital was used to measure the molar conductivity at 25 C for 10 -3 M solution of DMSO Micro elemental analysis(C.H.N.S) were performed using AcrloErba 1106 elemental analyzer. Magnetic susceptibility measurements were obtained by balance magnetic susceptibility model MSB-MKI. Metal contents of the complexes were determined by atomic absorption technique by using Shimadzu (AA680G ).

Method for the preparation of ligand.
The ligand was prepared by two steps(Scheme-1)

Scheme 1.Preparation way for the ligand (L)
The

Synthesis of the [Mn(L) 2 Cl 2 ] complex.
Add the ethanol solution (10ml) of MnCl 2 .4H 2 O (4.42g,26mmol) to the ethanol solution (10ml) of the ligand (6.50g,26mmol)(L) . The mixture was stirred for 6 hours at room temperature, and the dark green precipitate back was collected, washed with H 2 O and C 2 H 5 OH mixture (1:1) and recrystallized with C 2 H 5 OH and placed in an oven at 50C to dry.

Synthesis of [Co(L) 2 Cl 2 ], [Cd(L) 2 Cl 2 ], [Hg(L) 2 Cl 2 ]complexes.
The complexes of [Co( ,Cd( ) and Hg( )] ions with(L) were prepared in the same way as the manganese complex, Most of the physical data of all complexes are listed in the

4.The ligand complexes
By studying the prepared complexes, it was found to be thermally stable and dissolve in some solvents such as DMF,DMSO. From the data listed in the table (1), each the prepared complexes have the non-electrolytic nature of DMSO solvent in10 -3 M at 25 o C [16]. The theoretical and practical results of atomic absorption measurements for all prepared complexes were approximated

FT-IR Spectra of complexes
The FT-IR spectra showed various bands, Fig.(5) relationship to the stretch vibration of (CO amide) limit between(1625-1611)cm -1 shifted low frequencies by (74-60)cm -1 proposed the coordination of ligand by the(O atom) at the (CO group) [17].While the band give rise to by (CS)showed between (1238-1205)cm -1 shift to high frequencies by (70-37)cm -1 which due to the co-ordination of ligand by the (S atom) at the (thiol group) to the centric ion [18].

Biological Activity of the ligand (L] and its Complexes
The biological activity for the ligand(L) and its complexes were studied using inhibition method [25][26],two types of bacteria (+) (Staphylococcus aureu) and (-)( Escherichiacoli). In concentrations prepared, ligand (L) and its complexes display high efficacy to inhibit the spread of bacteria. The data obtained are found in the table(4), Fig.(7) The  Table 4. Showed the inhibition circle diameter for the bacteria after 24 hrs in cubation paid and 37 (C).

Diameter of inhibition zone (mm) Compound
Escherichia

Conclusion
The octahedral geometry of the prepared complexes was proposed on the basis of the spectral studies ( 1 H-13 C NMR for ligand(L)only),conductance and magnetic moment for the compounds. It is also found the ligand(L) exhibit as a bi dentate on co-ordination with Manganese( ), Cobalt( ),Cadmium(II) and Mercury( ) ions by(O atom) of (CO amide) and (S atom) of(CS thiol), Fig.(8).