Study of Stability Complex Formation of Transition Metals
with Chalcone
Kate Kashmira Hiralal and N. N. Pawar
Department of Chemistry,
S.S.V.P.S’s L. K. Dr. P. R. Ghogrey Science College, Dhule-424005, INDIA.
(Received on: December 23, 2016)
ABSTRACT
The interaction of Cu(II),Co(II),Cr(III) with
1] 2 hydroxy -3- nitro-5-chloro-4-nitro chalcone.(HNCNC) & 2] 2 hydroxy -5- chloro-2-nitro chalcone. (HCNC)
Have been studied by Calvin-Bejerrum titration technique in media of 70% dioxane water mixture at 0.1M ionic strength at 30 ±0.1°c temperature. Cu(II),Co(II),Cr(III) metal formed 1:1 and 1:2 complexes is occur simultaneously . In this probe the data obtained used to quote the value of proton-ligand and metal ligand formation constant in the order of Cu(II) < Co(II) < Cr(III).
Keywords: pH-metric study, Cu(II),Co(II),Cr(III), Metal Ligand, Stability constant, Substituted chalcone.
INTRODUCTION
Substituted chalcone is good chelating agent due to presence of electron donating oxygen atom (2, 3). Chalcone are aromatic ketone that forms the central core of various biological compounds. Chalcone and their metal ligand have demonstrated wide range of analytical and biological applications (4, 6, 7). It was interesting to know physicochemical properties such as stability of complexes with Cu(II),Co(II),Cr(III) metal ion pH-Metrically(1, 10, 11).Study of complexes under identical condition is still lacking. In present investigation chalcones prepared by conventional method (5, 8 9) are as below
Figure 2: 2 hydroxy -5- chloro-2-nitro chalcone (HCNC)
EXPERIMENTAL
All Chemicals such as NaOH, HNO3, and NaNO3 were of A R Grade. The ligands were prepared by literature method. The metal ions were used in the form of their nitrate.
Systronic scientific digital pH-Meter was used for measurement of pH. Standard NaOH and 1 M NaNO3 solution were prepared in double distilled water. PH-meter calibrated by standard buffer solution of pH 4.0, 7.0 and 9.20 at 30°c before processing the titration. The experimental procedure implies pH-metric titration as follow:
1] Free acid (0.01M)
2] Free acid (0.01M) + Ligand (20×10-4M)
3] Free acid (0.01M) + Ligand (20×10-4M) and Metal ion (4×10-4M) against standard NaOH solution (1.009N)
Titration was carried out in Pyrex beaker. The ionic strength of the solution was maintained (µ=0.1M) by adding appropriate quantity of 1M NaNO3.The readings were recorded for each addition of 0.2ml standard NaOH solution.
RESULT AND DISCUSSION
Proton-ligand stability constant of ligand
Substituted chalcones may be considered as monobasic acid having one dissociable H+ ion from OH¯ion .In present investigation monobasic ligand used and expressed as follow:
The titration data were used to construct the curve [acid curve (A)+ ligand curve (A+L) +Metal ion curve (A+L+M)]between volume of NaOH against pH.
Where,
𝛾- Number of dissociable protons from ligand E0 - Concentration of HNO
3 N - Normality of NaOH
V2 & V1 - Volume of alkali consumed by acid and ligand on same pH V0 - Initial Volume
TL0 - Ligand concentration
Table 1: Ligand L-1 (HNCNC) at the temperature 30±1°c
pH v1 v2 v2-v1 n-
2.42 2.44 2.48 0.06 0.058 2.52 2.54 2.58 0.06 0.135 2.62 2.64 2.68 0.06 0.27 2.72 2.74 2.78 0.06 0.404 2.82 2.84 2.88 0.06 0.485 2.9 2.92 2.96 0.06 0.577 3.92 3.94 3.98 0.06 0.752 3.12 3.14 3.18 0.06 0.936 3.22 3.24 3.28 0.06 1.068 3.33 3.35 3.39 0.06 1.231 3.32 3.34 3.38 0.06 1.379 3.52 3.54 3.58 0.06 1.496 3.62 3.64 3.68 0.06 1.65 3.72 3.74 3.78 0.06 1.801
Table 2: Ligand L2 (HCNC) at the temperature 30±1°c
pH v1 v2 v2-v1 n-
Table 3: Proton-Ligand Stability Constant at 30°c (𝝁 = 𝟎. 𝟏𝑴)
System pK
L1- HNCNC 8.2
L2- HCNC 8.82
Table 4: Ligand L-1 (HNCNC): Metal-Ligand Stability Constant at 30°c (𝝁 = 𝟎. 𝟏𝑴)
System log K1 log K2 logK1/logK2
L1- HNCNC Cu(II) 8.64 8.19 1.054945055 L1- HNCNC Co(II) 8.48 8.04 1.054726368 L1- HNCNC Cr(III) 8.09 8.01 1.009987516
Table 5: Ligand L2 (HCNC): Metal-Ligand Stability Constant at 30°c (𝝁 = 𝟎. 𝟏𝑴)
Graph 1: Ligand L-1 (HNCNC)
Graph 2: Ligand L-2 (HCNC)
System log K1 log K2 logK1/logK2
CONCLUSION
It could be observed from the tables given above that there is appreciable difference between log K1 and log K2 value. These indicate the formation of 1:1 and 1:2 complexes. During formation of metal chelates water molecule from the primary hydration sphere of the metal ion are replace by the chelating ligand. For this the solvent and ligand field interaction the order of stability constant for these metal complexes was: Cu(II) < Co(II) < Cr(III).
ACKNOWLEDGEMENT
The authors are thankful to Principal, Dr, D.A. Patil S.S.V.P.S’s L.K. Dr. P.R. Ghogrey Science Collage, Dhule for encouragement and providing necessary facilities.
REFERENCES
1.
Bjerrum J. Meetal amine formation in aqueous solution, P. Hasse and Sons. Copenhagen (1941).2.
Bouwmann E., Driessen W.L., Reedijk J., Coord. Chem. Rev. 104, 1432009 (1990).3.
Kornet M.J. and Carrett R.J., Synthesis of 1-phenyl-2-(phenylcarbamoyl) pyrazolidines as potential anticonvulsant agents. J Pharm Sci.; 68:313-318 (1979).4.
Lin, Y.M., Zhou Y., Flavin M.T., Zhou L.M., Nie W. and Chen F.C., Chalcones and flavonoids as anti- tuberculosis agents. Bioorg. Med. Chem., 10: 2795-2802 (2002).5.
Pathare U.A. and Thakur, Studies on interaction between Sm(III),and Nd(III) metal ions and novel chalcones at 0.1 M ionic strength pH metrically. Int. J. of Inn. Res. and Dev., Vol4(4),ISSN 2278-0211 (2015).6.
Procter I. M., Hathaway B. J., Billing D. E., Nicholls P., J. Chem. Soc. A, 1678 (1968).7.
Rahimizadeh M., Pordel M., Bakavoli M., Rezgeian S. and Sadghian A. Synthesis and antibacterial activity of some new derivatives of pyrazole. World J Microbiol Biotechnol, 26, 317-321 (2010).8.
Ramteke A. A., Chavan S. P., Patil S. D. and Narwade M. L. Effect of ionic Strength on the stability constants of complexes of 3-(4- Chlorophenyl)-4-(3-pyridine)-5-(2-hydroxyphenyl)-pyrazole with Cu(II), Tb(III) &Nd(III) metal ions. Int J Chem Studies, 2(4), 01-05 (2014).9.
Routh S. R. and Gollapalli N. R. Speciation of Binary Complexes of Co(II), Ni(II) and Cu(II) With Bidentate Ligand in Low Dielectric Medium. Int J Res Method In Phys and Chem, 1(1), 20-30 (2014).10.
Sharma Sangeeta, Shah M.C., Dalwadi Dipika, Thakkar Falguni and Vora J.J.; Res. J.Chem. Env., 12(4), 29-34 (2008).
