This document summarizes the synthesis and study of transition metal complexes of benzaldimino-1,3,4-thiadiazole-2-thiol (BTT). The author synthesized the ligand BTT and its copper, nickel, cobalt, and zinc complexes. The complexes were characterized using infrared spectroscopy, electronic spectroscopy, ESR, cyclic voltammetry, NMR, and magnetic susceptibility measurements. Spectroscopic data indicated the ligand behaves as a bidentate ligand, forming octahedral complexes with the metals. The author thanks advisors and colleagues and concludes the spectral studies support an octahedral geometry for the complexes.

1. SYNTHESIS AND STUDIES ON TRANSITION METAL COMPLEXES OF
BENZALDIMINO-1,3, 4-THIADIAZOLE -2-THIOL
MASTER OF SCIENCE IN CHEMISTRY
A. JEEVIKA
(REG.NO.09PC06)
DEPARTMENT OF CHEMISTRY
THIAGARAJAR COLLEGE (AUTONOMOUS
(Affilliated to Madurai kamaraj university)
MADURAI-625 009.
APRIL – 2011

2. INTRODUCTION
COORDINATION CHEMISTRY

The term coordination chemistry is generally used to describe
the chemistry of metals and metal ions in their interactions
with other molecules or ions .
 The chemistry of inorganic complexes is at present undergoing a
period of rapid development and is engaging the attention of
research worker in many diverse disciplines, both experimental
and theoretical progress in the area of chemistry .

3. we have designed a series of amino-substitution
compounds with electron withdrawing and electrondonating groups on both terminals of the two aromatic
substitution. Keeping this in view, we have
synthesized some new imine derivatives of 5-amino1,3,4-thiadiazole-2-thiol for their metal(II) complexes.

4. AIM AND SCOPE OF THE PROJECT
To prepare transition metal(II) complexes with
benzaldimino-
1,3,4-thiadiazole-2-thiol (BTT).
To prepare benzaldimino-1,3,4-thiadiazole-2-thiol
To characterize these complexes by physical and chemical and
spectral methods.
SCOPE
 Metal(II) Complexes behave as model compounds similar to bio
molecules, involved in electron transfer reactions, energy transfer
reaction, protein synthesis, oxygen carrier etc,.

5. EXPERIMENTAL METHODS
SYNT E OF L
H SIS
IGAND

Preparation of benzaldimino-1,3,4-thiadiazole-2-thiol (B T
T)

6. SYNTHESIS OF COMPLEXES
All complexes ( M = Cu(II), Ni(II), Co(II) and Zn(II)) were synthesized from
anhydrous metal(II) chlorides and the ligand. Anhydrous metal(II) chlorides were
prepared by dehydrating the metal chlorides at 150°C in oven for one hour.
 Synthesis of copper(II) complex
 Synthesis of nickel(II) complex
 Synthesis of cobalt(II) compleX
 Synthesis of zinc(II)complex

7. RESULTS AND DISCUSSIONS
IR spectral studies
Electronic spectral studies
ESR spectrum
Electro Chemical Behaviour
NMR studies
we have characterized our compound using above spectral
methods.

8. Magnetic moment and conductance of the metal complexes
S.No
Compound
Molecular
weight
Molar condctance (Λm)
Ω-1 cm2 mol-1
Magnetic
moment (µeff)
BM
1.
[Cu L2Cl2]
576.48
20.2
1.6
2.
[Ni L2Cl2 ]
571.60
18.9
2.7
3.
[Co L2Cl2]
571.93
21.2
4.2
4.
[Zn L2Cl2]
578.28
25.2
-

9. IR Spectral data of ligand(BTT) and their copper complex
S.No
Mode
of
viberation
Observed band
region (cm-1)
Ligand
Copper
1.
ν(S-H)
2668.03
-
2.
ν(C=N)
1540.85
1531.2
3.
ν(C=S)
1294.97
1281.47

10. IR Spectral data of ligand(BTT) and their copper
complex
S.No
Mode
of
viberation
Observed
band region (cm-1)
Ligand
Copper
1.
ν(S-H)
2668.03
-
2.
ν(C=N)
1540.85
1531.2
3.
ν(C=S)
1294.97
1281.47

11. Electronic spectral data of ligand(BTT) and their metal complexes
S.No
Compounds
Frequency
(cm-1)
Assignment
Geometry
Magnetic
Moment(µeff)
BM
1.
Ligand(BTT)
31152
38910
INCT
-
-
Distorted Oh
2.
[Cu L2Cl2]
14144
3.
[Ni L2Cl2 ]
10183
11415
3
4.
[Co L2Cl2]
10193
4
1.6
Eg→T2g
A2g (F)→3T2g ( F)
3
A2g (F) →3T1g (F)
Oh
2.7
T1g (F)→4A2g (F)
Octahedral
4.2

16. CYCLIC VOLTAMMETRIC DATA OF COPPER COMPLEX
S.No
Complex
Couple
Epa (v)
Epc (v)
Ipc (µA)
Ipa (µA)
1.
[Cu L2]Cl2
Cu(III)/Cu(II)
0.325
0.15
0.25
0.65

17. ESR Spectral Data of Copper and Complex in DMF at 77 K
Complex
A║
A┴
Aiso
g║
g┴
giso
[Cu L2Cl2]
160.0
82.05
160.42
2.85
2.29
2.286

18. ESR Spectrum of Copper Complex (CuL2)at 300 k
Complex
A║
A┴
Aiso
g║
g┴
giso
[Cu L2Cl2]
160.00
82.05
160.42
2.85
2.29
2.286

21. Nuclear Magnetic Resonance
1
H NMR spectra of the ligand in CDCl 3 shows following signals.

The signals due to aromatic at δ=7.3- 7.8 to showed fine
structure

CH=N azomethine proton at 8.08 ppm

S-H protons appears as singlet in the down field region at
11.8ppm.
C NMR spectra of the ligand in CDCl 3 shows
following signals.
13

The signals due to aromatic at 127-133 ppm showed fine
structure

C=N azomethine carbon at144 ppm

C-SH Carbon appears as singlet in the down field region
at178.6 ppm

22. Proposed structure of metal complex

23. Three Dimensional View of Metal Complexes

24. CONCLUSIONS
Spectral and magnetic moment measurement studies
reveals that the ligand behaves as a bidentate ligand
and form metal(II) complexes with octahedral geometry.
The ESR spectral data also are in supportive of the
above octahedral geometrical environment.

25. ACKNOWLEDGEMENTS
Dr.A.Thamarai selvan
Dr. M. Ganasan
 Dr .P. Tharmaraj
 Mrs. R . Shunmugakala
 Prof. A. Elangovan
 J.Athilakshmi, M. Manikkavalli
 B.Waheedha Banu and S. Priya
 My parents and my sister Jeevitha

26. Jeevika Alagan