research article synthesis and characterisation of new...

Research ArticleSynthesis and Characterisation of New SymmetricalBinucleating Ligands and Their Binuclear Copper(II) Complexes

K Jothivenkatachalam and S Chandra Mohan

Department of Chemistry Bharathidasan Institute of Technology Anna University Tiruchirappalli 620024 India

Correspondence should be addressed to K Jothivenkatachalam jothivenkatyahoocom

Received 17 August 2013 Revised 27 October 2013 Accepted 10 November 2013 Published 2 January 2014

Academic Editor Andrea Bencini

Copyright copy 2014 K Jothivenkatachalam and S Chandra Mohan This is an open access article distributed under the CreativeCommons Attribution License which permits unrestricted use distribution and reproduction in any medium provided theoriginal work is properly cited

New symmetrical binucleating ligands NN-bis[2-hydroxy-5-methyl-3-(4-methyl-piperazinomethyl)benzyl]-alkylamines L1 andL2 and their copper(II) complexes [Cu

2L(X)2]sdot2H2O where X = CH

3COOminus C

6H5COOminus Clminus and ClO

4

minus were prepared andcharacterised All the complexes undergo quasi-reversible reduction at negative potential (E = minus048 to minus102V) The acetate andbenzoate complexes undergo a two-step single electron transfer at ndash048 to ndash060V and minus09 to minus102VThe chloro and perchloratecomplexes undergo a single step two-electron transfer at minus055 to minus075V Variable temperaturemagnetic studies show the presenceof weak exchange interaction for acetate (minus2 J around 25 to 40 cmminus1) and benzoate (minus2 J around 45 to 55 cmminus1) bridged complexesand no exchange interaction is found for chloro and perchlorate complexes ESR spectra of chloro and perchlorate complexes arelike mononuclear copper(II) complexes with hyperfine splitting (A = 165 plusmn 5 119892

= 217ndash223 and 119892

perp= 205ndash210) The ESR spectra

of acetate and benzoate complexes are like binuclear copper(II) complexes with broad signal (119892 = 22)

1 Introduction

Interest in the synthesis of new binucleating ligands withdifferent donor atoms and flexibility [1ndash6] attracts the atten-tion of several coordination chemists because complexesprepared using these ligands emerge with peculiar chemicalbehaviours mainly due to their application in bioinorganicchemistry magnetochemistry electrochemistry and homo-geneous catalysis This interest has arisen because such lig-ands can accommodate two metal centers and thus may pro-vide the basis of models for the active sites of biological sys-tems Several bi- and polynuclear copper containing proteinshave been identified such as hemocyanin tyrosinase catecholoxidases ceruloplasmin laccase and ascorbate oxidase [7ndash15]Understanding the functional and structural properties ofbinuclear active site by developing small dicopper complexesas models for these metalloproteins is the main aim ofthe bioinorganic chemist In physicochemical aspects thesedicopper complexes have noteworthy significance as newinorganic materials capable of showing peculiar magneticand redox properties and hence these dinuclear copper(II)complexes have wealthy applications in magnetochemistry

and homogeneous catalysis [16ndash20] In our laboratory we aredealing with binucleating ligands and their metal complexesfor more than one decade So far we have synthesised seriesof binucleating ligands with phenolic and piperazinyl donoratoms [21ndash29] The magnetic and ESR spectral behavioursof the complexes are interesting The dicopper(II) complexesof the ligand ldquoardquo [21 22] are strongly antiferromagneticthe complexes of the ligand ldquobrdquo are weakly antiferromag-netic [23 24] and the complexes of the ligand ldquocrdquo areparamagnetic [25] as shown in Scheme 1 The present studydeals with the synthesis of similar compounds like ldquocrdquo inwhich the two 2-hydroxy-5-methyl-3-(4-methylpiperazinyl)-substituted phenyl residues are separated by a ndashCH

2ndashNndash

CH2ndash fragment instead of methylene group

2 Experimental

21 Materials and Methods All the chemicals and reagentsused in this study were obtained from Merck and SigmaAldrich Tetra-N-butyl ammonium perchlorate was pur-chased from Fluka and recrystallised from ethanol-water

Hindawi Publishing CorporationJournal of Inorganic ChemistryVolume 2014 Article ID 461546 9 pageshttpdxdoiorg1011552014461546

2 Journal of Inorganic Chemistry

CH3CH3

CH3

OH

N N

NN

R = CH3C2H5

CH3 CH3

CH3CH3

OHOH

N N

N N

N

R

(a)

CH3

CH3

CH3

H3C

H3C

OH

OH

N

NN

(b)

CH3

CH3

CH3

CH3

OH

OH

N

N

N

N

(c) (d)

Scheme 1

mixture (caution TBAP is potentially explosive hence careshould be taken in the handling of this compound) HPLCgrade dimethylformamide and acetonitrile were obtainedfrom SD Fine chemicals

22 Physical Measurements Elemental analyses were carriedout by using Carlo Erba model 1106 elemental analyserAtomic absorption spectra were recorded on Varian AA-200 model atomic absorption spectrophotometer 1H NMR(90MHz) spectra were recorded in CDCl

3using a FX-90Q

Fourier transform NMR spectrometer 13C-NMR spectra(200MHz) were recorded on a JEOL model 400 NMRspectrometer and the EI mass spectra were recorded on aJMSDX303-HFmass spectrometer IR spectra were recordedon a Hitachi 320 spectrophotometer on KBr disks in therange 250ndash4000 cmminus1 Electronic spectra were recorded ona Hewlett-Packard 8452 A diode array spectrophotometerin the range 250ndash850 nm Molar conductivity measurements

were measured on an Elico digital conductivity bridge modelM88 and conventional cell which was previously calibratedwith an aqueous solution of KCl (01 N)

For cyclic voltammetry a three-electrode system wasused in which the counter and working electrode were smallplatinum foils and saturated AgAgCl was the reference elec-trode TBAP was used as the supporting electrolyte (01M)and all the solutions were around 10minus3M in concentrationThe cyclic voltammograms were obtained on an appara-tus comprising a PAR model-173 potentiostatgalvanostatmodel-175 universal programmer model-176 coulometerand a Perkin-Elmer Hitachi (057) X-Y recorder The mea-surements were carried out inDMFunder oxygen free condi-tions Variable temperaturemagnetic studies were performedon PARmodel-155 vibrating samplemagnetometer operatingat 5000 gauss and the instrument was calibrated with metal-lic nickel supplied with the instrument ESR spectra wererecorded using a Bruker ER-200D-SRC spectrometer

Journal of Inorganic Chemistry 3

OH OH OH

N

R

OH OH

N

R

N

NN

N

PC

N-MethylpiperazineHCHO

Cu(II) salt

N NR

O

O

N

Cu

Cu

XX

N

N

CuN

N

N

N

O

O

O

O

C

R

N

2 2 + 2HCHO 2 1 2

1 2 2

CH3

CH3CH3

CH3

CH3 CH3

H3C

(2M)

Cu(II) salt + NaX

(X = OAc OBz)

L1 and L2

L1-R = CH3

L2-R = C2H5

Cu

R1

R = CH3 C2H5

X = ClClO4

R = CH3 C2H5

R1 = CH3 C6H5

CH3

CH3

CH3 CH3

2 1

+ RndashNH

Figure 1 Schematic diagram for the synthesis of ligands and complexes

23 Synthesis of the Ligand The ligands L1 and L2 wereprepared by following a two-step procedure In the first stepNN-bis[2-hydroxy-5-methylbenzyl]methylamine (PC1) andNN-bis[2-hydroxy-5-methylbenzyl]ethylamine (PC2) wereprepared by reacting p-cresol paraformaldehyde and pri-mary amines in 2 2 1 ratio in ethanol medium by followingthe literature procedure [30] In the second step these com-pounds (PC1 and PC2) were aminoalkylated according to theMannich reaction with N-methylpiperazine and formalinThe schematic diagram for the synthesis of the ligands andcomplexes is shown in Figure 1

231 NN-Bis[2-hydroxy-5-methyl-3-(4-methylpiperazino-methyl)benzyl]methylamine L1 Paraformaldehyde (075 g0025mol) was taken in 150mL of glacial acetic acid and

allowed to stir for 4 hours To this N-methylpiperazine(23mL 002mol) was added and stirring was continued for24 hours The NN-bis[2-hydroxy5-methylbenzyl] methyl-amine (271 g 001mol) was added and stirred for 48 hoursThe resulting solution was kept at 75∘C for about 3 hoursIt was cooled and neutralised using saturated Na

2CO3 A

pasty product obtained was thoroughly washed using dis-tilled water Then it was extracted using dichloromethane(350mL) The extracted was treated with activated char-coal and filtered The filtrate was evaporated A pale yel-low oily substrate separated was recrystallised in benzene-ethanol mixture and dried under vacuum Mp 71∘C13C-NMR-(CDCl

3200MHzTMS) 120575 = 157 203 (ndashCH

3)

406 530 548 556 578 and 600 (benzylic carbons)1223 1225 1244 1280 1307 and 1555 (aromatic carbons)


1H-NMR (CDCl390MHzTMS) 120575 = 113 (t 3H) 221 (s 6H

and N-CH3) 226 (s 6H and Ar-CH

3) 252 (br 16H and

piperazinyl protons) 36 (two close singlets 8H benzylic)and 67ndash70 (m 4H and Ar-H) Mass (EI) mz = 496 (M +1) Anal Calcd for C

29H45N5O2() C 703 H 91 N 141

Found C 701 H 92 N 142

232 NN-Bis[2-hydroxy-5-methyl-3-(4-methyl-piperazino-methyl)benzyl]ethylamine L2 The above procedure wasused for the preparation of this compound using NN-bis[2-hydroxy-5-methylbenzyl]ethylamine instead of NN-bis[2-hydroxy-5-methylbenzyl]methylamine Mp 79∘C 13C-NMR-(CDCl

3200MHzTMS) 120575 = 73 (ali-CH

3) 156 and

158 (N-CH3and N-CH

2) 203 (Ar-CH

3) 406 546 552

558 578 and 601 (benzylic carbons) and 1223 12261244 1281 1308 and 1554 (aromatic carbons) 1H-NMR(CDCl

390MHzTMS) 120575 = 113 (t 3H and CH

3of ethyl

group) 221 (s 6H and N-CH3) 226 (s 6H and Ar-CH

3)

252 (br 18H piperazinyl and CH2protons of ethyl group)

36 (two close singlets 8H and methylene protons) and67ndash70 (m 4H and Ar-H) Mass (EI) mz = 510 (M + 1)Anal Calcd for C

30H47N5O2() C 707 H 92 N 138

Found C 707 H 92 N 137

24 Synthesis of Copper(II) Complexes

241 [Cu2L1(OAc)]ClO4sdot2H2O (1) To a hot methanol-dichloromethane (2 1 50 25 vv) solution of the ligand L1(10 g 2mmol) copper(II) perchlorate hexahydrate (148 g4mmol) was added and the mixture was refluxed on a waterbath for 2 hours Then sodium acetate trihydrate (27216 g2mmol) dissolved in minimum amount of water was addedand refluxed for one more hour The resulting solution wasfiltered and kept at room temperature for few days Thegreen precipitate separated was filtered off washed with coldmethanol and a little diethyl ether and dried under vacuumYield 115 g (706) Anal Calcd for C

31H50ClCu2N5O10

() C 457 H 61 Cu 156 N 86 Found C 451 H 60Cu 155 N 84

242 [Cu2L2(OAc)]ClO4sdot2H2O (2) The above procedurewas used for the preparation of this complex using lig-and L2 (1018 g 2mmol) instead of ligand L1 Greensolid was obtained Yield 117 g (70) Anal Calcd forC32H52ClCu2N5O10

() C 464 H 63 Cu 154 N 84Found C 459 H 61 Cu 153 N 82

243 [Cu2L1(Benz)]ClO4sdot2H2O (3) and [Cu2L2(Benz)]ClO4sdot2H2O (4) The procedure used for the preparation ofthese complexes is same as that of [Cu

2L1 (OAc)]ClO

4sdot2H2O

Here sodium benzoate (0298 g 2mmol) was used insteadof sodium acetate The reaction was carried in methanol-dichloromethane mixture Dark green solid colour wasobtained Yield 132 g (7542) for (3) Anal Calcd forC36H52ClCu2N5O10

() C 493 H 59 Cu 144 N 80Found C 493 H 59 Cu 143 N 80 Dark green solidcolour was obtained Yield 140 g (786) for (4) Anal Calcd

for C37H54ClCu2N5O10() C 499 H 60 Cu 1426 N 79

Found C 496 H 61 Cu 143 N 77

244 [Cu2L1(Cl)2]sdot2H2O (5) To a hot methanolic solution(100mL) of the ligand L1 (10 g 2mmol) copper(II) chloridedihydrate (3409 g 4mmol) was added to dissolved distilledmethanol (50mL) and the mixture was refluxed on a waterbath for 2 hours The resulting yellowish green solution wasevaporated at room temperature for several days filtered offwashed with water followed by little diethyl ether and driedunder vacuum Yellowish green precipitate was obtainedYield 095 g (655) Anal Calcd for (5) C

29H47Cl2Cu2N5O4

() C 479 H 65 Cu 174 N 96 Found C 478 H 64 Cu173 N 97

245 [Cu2L2(Cl)2]sdot2H2O (6) This complex was preparedby following the above procedure using ligand L2 (1018 g2mmol) instead of ligand L1 Green solid colour wasobtained Yield 105 g (709) Anal Calcd for (6)C30H49Cl2Cu2N5O4

() C 486 H 66 Cu 174 N944 Found C 485 H 66 Cu 173 N 94

246 [Cu2L1(ClO4)2]sdot2H2O (7) This complex was preparedby following the procedure adopted for the preparation of(1) and no sodium acetate was added Dark green solidcolour was obtained Yield 121 g (708) Anal Calcd For(7) C29H47Cl2Cu2N5O12() C 407 H 55 Cu 149 N 82

Found C 406 H 54 Cu 148 N 813

247 [Cu2L2(ClO4)2]sdot2H2O (8) The above procedure wasused using ligand L2 (1018 g 2mmol) instead of ligand L1Dark green-coloured product formed was filtered washedwith water and dried under a vacuum Yield 115 g (664)Anal Calcd for (8) C

30H49Cl2Cu2N5O12() C 414 H 56

Cu 147 N 81 Found C 413 H 56 Cu 146 N 80All these complexes (1ndash8) are recrystallised and not able

to obtain crystals suitable for X-ray studies

3 Results and Discussion

The ligands (L1 and L2) were characterised by analyticalmethod and mass spectral studies In the 1H-NMR spectrathe peaks for aromatic hydrogens appear around 120575 = 67ndash70 benzylic protons appear around 120575 = 36 N-methyl ofthe piperazine residue and aromatic methyl protons appeararound 120575 = 22 piperazinyl protons appear as a broad peakin the region 120575 = 25 and the aliphatic methyl protons appearat 120575 = 113 In the 13C-NMR signals for the aliphatic carbonatoms were observed in the region 120575 = 7 to 61 and the signalsfor the aromatic carbon atoms were observed in the region120575 = 121 to 156The IR spectra of all the complexes show broadbands in the region around 3450 cmminus1 indicating the presenceof coordinated or lattice water in the complexes [25 26]Characteristic peak for acetate was observed at 1540 cmminus1 andpeak for the perchlorate anion was observed at 1100 cmminus1


Table 1 Electronic spectral data for the complexes (in methanol)

No Complexes d-d LMCT LLCT[120582max (nm) (120576 Mminus1 cmminus1)]

1 [Cu2L1(OAc)]ClO4sdot2H2O 650 (184) 388 (1270) 288 (15 800)

248 (19 500)


246 (19 700)

3 [Cu2L1(Benz)]ClO4sdot2H2O 650 (143) 390 (687) 292 (10 900)

242 (18 600)


248 (17 200)

5 [Cu2L1Cl2]sdot2H2O 650 (290) 420 (1310) 284 (14 100)

244 (19 800)

6 [Cu2L2Cl2]sdot2H2O 638 (249) 412 (540) 286 (12 500)

238 (13 000)

7 [Cu2L1(ClO4)2]sdot2H2O 657 (208) 405 (sh) 287 (14 700)

235 (16 300)8

[Cu2L2(ClO4)2]sdot2H2O 658 (192) 410 (sh) 285 (13 300)

234 (14 900)CT charge transfer Sh shoulder

Table 2 Electrochemical data for the complexes (in dmfa)

No Complexes 119864

1 pcv 119864

1 pav 119864

1

12v

(Δ119864mv) 119864

2 pcv 119864

2 pav 119864

2

12V

(Δ119864mv)1 [Cu2L

1(OAc)]ClO4sdot2H2O minus052 minus036 minus044 (160) minus094 minus070 082 (240)2 [Cu2L

2(OAc)]ClO4sdot2H2O minus058 minus042 minus050 (160) minus091 minus075 minus080 (160)3 [Cu2L

1(Benz)]ClO4sdot2H2O minus050 minus034 minus042 (160) minus098 minus074 minus086 (240)4 [Cu2L


1Cl2]sdot2H2O minus066 minus052 minus059 (140) mdash mdash mdash6 [Cu2L


1(ClO4)2]sdot2H2O minus068 minus050 minus059 (180) mdash mdash mdash8 [Cu2L

2(ClO4)2]sdot2H2O minus070 minus048 minus059 (220) mdash mdash mdashaPotential V versus SCE Conditions Pt working and SCE reference electrodessupporting electrolyte TBAP concentration complex (1 times 10minus3M) TBAP (1 times 10minus1M)

31 Electronic Spectra Electronic spectra of all the complexeswere studied in methanolic medium and the data are sum-marised in Table 1 For dicopper complexes the absorptionspectra exhibit three main features two high energy intensepeaks below 300 nm assigned to the intraligand charge trans-fer transitions (LLCT) a peak or shoulder around 400 nm(120576 asymp 2000 dm3molminus1) due to phenolate to copper chargetransfer transitions (LMCT) [31ndash34] and weak band around630ndash670 nm (120576 asymp 300 dm3molminus1) for the usual copper d-dtransitions

32 Electrochemistry The electrochemical behaviour of thecomplexeswas studied by cyclic voltammetry and the electro-chemical data such as cathodic peak potential (119864

119901119888) anodic

peak potential (119864119901119886) peak separation (Δ119864

119901) and redox

potential 11986412

are given in Table 2 The typical cyclic voltam-mogram for the complexes 2 and 8 is given in Figure 2 Thecyclic voltammogram of the complexes bridged by acetateand benzoate exogenous donor atoms shows twowell defined

quasi-reversible redox waves in the potential range minus02 tominus12 V However for the chloro and perchlorate complexesonly one redox wave in the potential range minus055 to minus075Vwas observed In order to ascertain the mechanism of theelectrochemical reduction coulometric measurement wascarried out At a potential minus110 V the acetate and benzoatecomplexes consumed 2 electrons per mole of the complexes(119899 = 194) and at a potential minus070V the complexesconsumed only one electron (119899 = 095) per molecule whichindicate that the involvement of two single electron transfersin the reduction processes of these complexes Based on thecoulometric results the two reduction peaks observed in thecyclic voltammograms are attributed to the two stepwise oneelectron transfers as observed in several binuclear copper(II)complexes [30 35] Consider

Cu (II)Cu (II)eminus999445999468 Cu (II)Cu (I)

eminus999445999468 Cu (I)Cu (I) (1)

The coulometric studies of the chloro and perchloratebridged complexes at a ndash085V indicate that the complexes


Table 3 ESR spectral and magnetic data for the complexesa

No Complexes 120583

120573Cu at 298K minus2 Jcmminus1 119892-values P A 119892 from ESR

119892

119892

perp

1 [Cu2L1(OAc)]ClO4sdot2H2O 156 26 220 0003 mdash mdash mdash


3 [Cu2L1(Benz)]ClO4sdot2H2O 145 53 220 0001 mdash mdash mdash


5 [Cu2L1Cl2]sdot2H2O 172 mdash mdash mdash 165 217 205


7 [Cu2L1(ClO4)2]sdot2H2O 171 mdash mdash mdash 160 220 210


a119873120572 has been fixed as 120 times 10minus6 cm3mole for all magnetic simulations

30120583A

Curr

ent

0 minus02 minus04 minus06 minus08 minus10 minus12 minus14

Potential V versus AgAgCl

(a)

0 minus02 minus04 minus06 minus08 minus10 minus12


25120583A

Curr

ent

(b)

Figure 2 Cyclic voltammogram for the complexes (a) [Cu2L2(OAc)]ClO

4sdot2H2O (2) and (b) [Cu

2L2(ClO

4)2]sdot2H2O (6)

consumed two electrons per molecule (119899 = 186) showingtypical electrochemical behaviour of remote donor set cop-per(II) complexes [36 37] Consider

Cu (II)Cu (II)2eminus999445999468 Cu (I)Cu (I) (2)

A comparison of the reduction potentials of the com-plexes of a particular ligand indicates that the reductionpotential is exogenous bridging donor dependent Acetateand benzoate bridged complexes undergo two-step singleelectron transfer whereas chloro and perchlorate complexesundergo single step two-electron transfer

33 Magnetochemistry Room temperature as well as variabletemperature (77ndash300K) magnetic studies were performedfor all the complexes and the magnetic data are given inTable 3 The magnetic data obtained from variable temper-ature magnetic studies were fitted to the modified Bleaney-Bowers equation [38 39] to evaluate the singlet-triplet energyseparation (minus2 J) Consider

120594

119898= (

119873119892

2120573

2

3119896119879

) [3 + exp(minus2 J119896119879

)]

minus1

(1 minus 119901) +

045119901

119879

+ 119873

120572

(3)

where 120594119898

is the molar magnetic susceptibility 119901 is thepercentage of monomeric impurities and other symbolshave their usual meanings 119873

120572has been fixed at 120 times

10minus6 cm3molminus1 and based on ESR studies 119892 was fixed as220 for all magnetic simulations minus2 J values were evaluatedby a nonlinear regression analysis in which minus2 J and 119901 arethe variables The variation of the magnetic properties withtemperature is given in Figure 3

The room temperature magnetic moment value of thecomplexes 1ndash4 shows lower 120583120573Cu values (minus2 J around 25 to40 cmminus1 for acetate minus2 J around 45 to 55 cmminus1 for benzoatecomplexes) than the spin only value but for the complexes 5ndash8 it shows that 120583120573Cu values are close to the spin only values

34 ESR Spectra Both room temperature and liquid nitrogentemperature ESR spectra of the complexes were recorded inDMF and the 119892-values were evaluated using the relationshipℎ] = 119892120573119867 shown in Table 3 The ESR spectra of thecomplexes 1 and 8 are shown in Figure 4 In the roomtemperature ESR spectra the complexes 1ndash4 show a broadband centered at 119892-220 but the complexes 5ndash8 show poorlyresolved hyperfine splitting signals (119892

= 217ndash223 and 119892

perp=

205 to 210) which are typical of mono nuclearcopper(II)


0 100 200 300 40005

10

15

20

05

10

15

20

Temperature (K)

120583eff

(BmiddotM

)

120594m

(times103

cm3

Mminus1)

Figure 3 Temperature dependence magnetic properties of thecomplex [Cu

2L1(OAc)]ClO

4sdot2H2Osdot (1)

2400 2800 3200 3600 4000Magnetic field (gauss)

(a)

(b)

200G

Figure 4 ESR Spectra for the complexes (a) [Cu2L1(OAc)]

ClO4sdot2H2O (1) and (b) [Cu

2L2(ClO

4)2]sdot2H2O (8)

complexes and no change in the intensity of the signal atliquid nitrogen temperature was observed [25 26 36]

4 Conclusion

Comparison of the coulometric magnetic and ESR spec-tral studies indicates that in the complexes the chemicalbehaviour varies depending upon the nature of the exoge-nous donor atoms The electrochemical studies of thesecomplexes indicate that all the complexes undergo quasi-reversible reduction at negative potential in the range of119864 = minus048 to minus120V The acetate and benzoate exogenousligand complexes behave like a bridged binuclear systemdue to the presence of OndashCndashO bridging unit Chloro andperchlorate ligand complexes do not form bridged binuclearcomplexes because of weak bridging capabilities of theseligands Magnetic properties of these complexes indicatethat there is a interaction for acetate and benzoate bridged

complexes and there is no exchange interaction for chloro andperchlorate complexes All these data indicate that the chloroand perchlorate complexes are not bridged but the acetateand benzoate complexes are bridged

Comparison of the chemical behaviour of the complexesof c with the present ligand d is also interesting Theunit which unites the two 2-hydroxy-5-methyl-3-(4-methyl-piperazinyl)-substituted phenyl residues in c is ndashCH

2and in d

the unit is ndashCH2ndashNndashCH

2 The X-ray structures of the ligand

c and similar compound of PC of ligand b are relatively that ofligand d [19 21] In c both units are anti therefore there is nopossibility to form bridged binuclear complexes but in d thetwo phenolic residues are cis and the flexibility of the ndashCH

2ndash

NndashCH2ndash linkage may allow the molecules to come closer in

the complexes of the ligand d leading to weak interactionbetween the copper atoms and in the case of ligand suchas chloride or perchlorate formation of a bridge betweenthe two copper atoms seems to be not possible hence theybehave as mononuclear complexes

Conflict of Interests

The authors declare that there is no conflict of interests

Acknowledgment

The authors thank the Department of Science and Technol-ogy (DST) Government of India New Delhi for financialsupport Sanction no SRFTCS-0422008

References

[1] H Holden Thorp and V L Pecoraro Mechanistic BioinorganicChemistry American Chemical SocietyWashington DC USA1995

[2] K D Karlin and J Tyekler Bioinorganic Chemistry of CopperChapman and Hall New York NY USA 1993

[3] K D Karlin and Y Gultneh ldquoBinding and activation ofmolecular oxygen by copper complexesrdquo Progress in InorganicChemistry vol 35 pp 219ndash327 1987

[4] N Sengottuvelan D Saravanakumar S Sridevi V Narayananand M Kandaswamy ldquoMacrocyclic unsymmetrical binuclearCopper(II) complexes as ligands spectral structural magneticand electrochemical studiesrdquo Supramolecular Chemistry vol 16no 2 pp 129ndash136 2004

[5] W Kaimand and J Rall ldquoCoppermdasha ldquomodernrdquo bioelementrdquoAngewandte Chemie vol 35 no 1 pp 43ndash60 1996

[6] E I Solomon U M Sundaram and T E Machonkin ldquoMulti-copper oxidases and oxygenasesrdquoChemical Reviews vol 96 no7 pp 2563ndash2605 1996

[7] O Kahn ldquoMolecular engineering of coupled polynuclear sys-tems orbital mechanism of the interaction between metalliccentersrdquo Inorganica Chimica Acta vol 62 pp 3ndash14 1982

[8] O Kahn Molecular Magnetism Wiley-VCH New York NYUSA 1993

[9] R J Butcher G Diven G Erickson G M Mockler andE Sinn ldquoCopper complexes of binucleating NN1015840-hydroxy-alkyldiaminebis(salicylidine) ligands containing a CuOCu


bridge and an exogenous bridgerdquo Inorganica Chimica Acta vol111 no 2 pp L55ndashL56 1986

[10] R J Butcher G M Mockler and E Sinn ldquoModel compoundsfor the type III site and the combined type II and type III sitesin multicopper oxidasesrdquo Proceedings of the Indian Academy ofSciences vol 102 p 209 1990

[11] P A Vigato S Tamburini and D E Fenton ldquoThe activationof small molecules by dinuclear complexes of copper and othermetalsrdquo Coordination Chemistry Reviews vol 106 pp 25ndash1701990

[12] H W Lee N Sengottuvelan H-J Seo et al ldquoStructuraland magnetic properties of monomeric and dimericCopper(II) complexes with phenyl-N-[(pyridine-2-yl)methylene]methaneamiderdquo Bulletin of the Korean ChemicalSociety vol 29 no 9 pp 1711ndash1716 2008

[13] S Anbu M Kandaswamy P Sathya Moorthy M Balasubra-manian and M N Ponnuswamy ldquoNew polyaza macrobicyclicbinucleating ligands and their binuclear copper(II) complexeselectrochemical catalytic and DNA cleavage studiesrdquo Polyhe-dron vol 28 no 1 pp 49ndash56 2009

[14] S Anbu M Kandaswamy P Suthakaran V Murugan andB Varghese ldquoStructural magnetic electrochemical catalyticDNA binding and cleavage studies of new macrocyclic binu-clear copper(II) complexesrdquo Journal of Inorganic Biochemistryvol 103 no 3 pp 401ndash410 2009

[15] G S Siluvai and N N Murthy ldquoX-ray structure and spectro-scopic characterization of doubly-bridged binuclear copper(II)complexes in symmetric and asymmetric coordination environ-mentsrdquo Polyhedron vol 28 no 11 pp 2149ndash2156 2009

[16] K D Karlin C X Zhang A L Rheingold B Galliker SKaderli and A D Zuberbuhler ldquoReversible dioxygen bindingand arene hydroxylation reactions kinetic and thermodynamicstudies involving ligand electronic and structural variationsrdquoInorganica Chimica Acta vol 389 pp 138ndash150 2012

[17] U Casellato P A Vigato D E Fenton and M VidalildquoCompartmental ligands routes to homo- and hetero-dinuclearcomplexesrdquo Chemical Society Reviews vol 8 no 2 pp 199ndash2201979

[18] P I Clemenson ldquoThe chemistry and solid state propertiesof nickel palladium and platinum bis(maleonitriledithiolate)compoundsrdquoCoordination Chemistry Reviews vol 106 pp 171ndash203 1990

[19] P Zanello S Tamburini P A Vigato and G A MazzocchinldquoSyntheses structure and electrochemical characterization ofhomo- and heterodinuclear copper complexes with compart-mental ligandsrdquo Coordination Chemistry Reviews vol 77 pp165ndash273 1987

[20] T N Somell ldquoSynthetic models for binuclear copper proteinsrdquoTetrahedron vol 45 no 1 pp 3ndash68 1989

[21] T M Rajendran Synthesis characterization and electrochemicalstudies of Copper(II) complexes [PhD thesis] University ofMadras 1992

[22] K Bertoncello J H Hodgkin and K S Murray ldquoExogenousbridging and nonbridging in copper(II) complexes of a binucle-ating 26-bis((N-methylpiperazino)methyl)-4-chlorophenolateligand Crystal structures and magnetic properties of bis(mu-acetato) dinitrito and bis(azido) complexes Possible relevanceto the type 3 depleted laccase active siterdquo Inorganic Chemistryvol 27 pp 4750ndash4758 1988

[23] P Amudha M Thirumavalavan and M Kandaswamy ldquoSyn-thesis spectral electrochemical and magnetic properties of

new phenoxo-bridged dicopper(II) complexes derived fromunsymmetrical binucleating ligandsrdquo Polyhedron vol 18 no 8-9 pp 1363ndash1369 1999

[24] PAmudha PAkilan andMKandaswamy ldquoSynthesis spectralelectrochemical and magnetic properties of new symmetricaland unsymmetrical dinuclear copper(II) complexes derivedfrom binucleating ligands with phenol and benzimidazoledonorsrdquo Polyhedron vol 18 no 8-9 pp 1355ndash1362 1999

[25] P Kamatchi and M Kandaswamy ldquoSynthesis and characterisa-tion of copper(II) complexes derived from methylene bridgedbis(tridentate) ligandsrdquo Polyhedron vol 17 no 8 pp 1397ndash14051998

[26] S Annapoorani ldquoSynthesis and spectroscopic characterizationof some Copper(II) trinuclear complexes involving Nitrogen asbridging atomsrdquo Asian Journal of Chemistry vol 24 no 8 pp3347ndash3351 2012

[27] P P Amudha M Kandaswamy L Govindasamy and B Velu-murugan ldquoSynthesis and characterization of new symmetricalbinucleating ligands and their 120583-phenoxo-bridged bicopper(II)complexes structural electrochemical and magnetic studiesrdquoInorganic Chemistry vol 37 no 18 pp 4486ndash4492 1998

[28] S Karunakaran and M Kandaswamy ldquoSynthesis electrochem-ical and magnetic properties of a series of new unsymmetricalmacrocyclic binuclear copper(II) complexesrdquo Journal of theChemical Society Dalton Transactions no 10 pp 1595ndash15981994

[29] S Karunakaran and M Kandaswamy ldquoSynthesis electrochem-ical and magnetic properties of new acyclic ldquoside-offrdquo binuclearcopper(II) complexesrdquo Journal of the Chemical Society DaltonTransactions no 11 pp 1851ndash1855 1995

[30] W J Bruke E L Marhensen Glennie and C WeatherbeeldquoCondensation of halophenols with formaldehyde and primaryaminesrdquo The Journal of Organic Chemistry vol 29 no 4 pp909ndash912 1962

[31] B J Hathway and G Wilkinson Comprehensive CoordinationChemistry John Wiley amp Sons New York NY USA 1985

[32] A B P Lever Inorganic Electronic Spectroscopy Elsevier Ams-terdam The Netherlands 2nd edition 1984

[33] S S Hindo R Shakya R Shanmugam M J Heeg and C NVerani ldquoMetalloamphiphiles with [Cu

2] and [Cu

4] headgroups

syntheses structures langmuir films and effect of subphasechangesrdquo European Journal of Inorganic Chemistry no 31 pp4686ndash4694 2009

[34] C N Verani R Shanmugam F R XavierMM Allarda andKK Kpogoa ldquoElectronic and interfacial behavior of gemini met-allosurfactants with copper(II)pseudohalide cascade coresrdquoDalton Transactions vol 42 no 43 pp 15296ndash15306 2013

[35] W Mazurek A M Bond K S Murray M J OrsquoConnorand A G Wedd ldquoPreparation and spectral magnetic andelectrochemical characterization of a flexible phenoxo-bridgedbinuclear copper(II) complexrdquo Inorganic Chemistry vol 24 no16 pp 2484ndash2490 1985

[36] C L Chuang K Lim Q Chen J Zubreta and J M CararyldquoSynthesis cyclic voltammetry and x-ray crystal structuresof Copper(I) and Copper(II) complexes of tris((6-phenyl-2-pyridyl)methyl)amine (TPPA)rdquo Inorganic Chemistry vol 34no 10 pp 2562ndash2568 1995

[37] C Fraser and B Bosnich ldquoBimetallic reactivity Investigationof metal-metal interaction in complexes of a chiral macrocyclicbinucleating ligand bearing 6- and 4-coordinate sitesrdquo InorganicChemistry vol 33 no 2 pp 338ndash346 1994


[38] B Bleaney and K D Bowers ldquoAnomalous paramagnetism ofCopper acetaterdquo Proceedings of the Royal Society A vol 214 no1119 pp 451ndash465 1952

[39] M Yonemura Y Matsumura H Furutachi M Ohba HOkawa and D E Fenton ldquoMigratory transmetalation in di-phenoxo-bridged CuIIMII complexes of a dinucleating macro-cyclewithN(amine)

2O2andN(amine)

2O2metal-binding sitesrdquo

Inorganic Chemistry vol 36 no 13 pp 2711ndash2717 1997

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Inorganic ChemistryInternational Journal of

Hindawi Publishing Corporation httpwwwhindawicom Volume 2014

International Journal ofPhotoenergy


Carbohydrate Chemistry

International Journal of


Journal of

Chemistry


Advances in

Physical Chemistry

Hindawi Publishing Corporationhttpwwwhindawicom

Analytical Methods in Chemistry

Journal of

Volume 2014

Bioinorganic Chemistry and ApplicationsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

SpectroscopyInternational Journal of


The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Medicinal ChemistryInternational Journal of


Chromatography Research International


Applied ChemistryJournal of



Theoretical ChemistryJournal of


Journal of

Spectroscopy

Analytical ChemistryInternational Journal of


Journal of


Quantum Chemistry


Organic Chemistry International

ElectrochemistryInternational Journal of



CatalystsJournal of


CH3CH3

CH3

OH

N N

NN

R = CH3C2H5

CH3 CH3

CH3CH3

OHOH

N N

N N

N

R

(a)

CH3

CH3

CH3

H3C

H3C

OH

OH

N

NN

(b)

CH3

CH3

CH3

CH3

OH

OH

N

N

N

N

(c) (d)

Scheme 1

mixture (caution TBAP is potentially explosive hence careshould be taken in the handling of this compound) HPLCgrade dimethylformamide and acetonitrile were obtainedfrom SD Fine chemicals

22 Physical Measurements Elemental analyses were carriedout by using Carlo Erba model 1106 elemental analyserAtomic absorption spectra were recorded on Varian AA-200 model atomic absorption spectrophotometer 1H NMR(90MHz) spectra were recorded in CDCl

3using a FX-90Q

Fourier transform NMR spectrometer 13C-NMR spectra(200MHz) were recorded on a JEOL model 400 NMRspectrometer and the EI mass spectra were recorded on aJMSDX303-HFmass spectrometer IR spectra were recordedon a Hitachi 320 spectrophotometer on KBr disks in therange 250ndash4000 cmminus1 Electronic spectra were recorded ona Hewlett-Packard 8452 A diode array spectrophotometerin the range 250ndash850 nm Molar conductivity measurements

were measured on an Elico digital conductivity bridge modelM88 and conventional cell which was previously calibratedwith an aqueous solution of KCl (01 N)

For cyclic voltammetry a three-electrode system wasused in which the counter and working electrode were smallplatinum foils and saturated AgAgCl was the reference elec-trode TBAP was used as the supporting electrolyte (01M)and all the solutions were around 10minus3M in concentrationThe cyclic voltammograms were obtained on an appara-tus comprising a PAR model-173 potentiostatgalvanostatmodel-175 universal programmer model-176 coulometerand a Perkin-Elmer Hitachi (057) X-Y recorder The mea-surements were carried out inDMFunder oxygen free condi-tions Variable temperaturemagnetic studies were performedon PARmodel-155 vibrating samplemagnetometer operatingat 5000 gauss and the instrument was calibrated with metal-lic nickel supplied with the instrument ESR spectra wererecorded using a Bruker ER-200D-SRC spectrometer


OH OH OH

N

R

OH OH

N

R

N

NN

N

PC


Cu(II) salt

N NR

O

O

N

Cu

Cu

XX

N

N

CuN

N

N

N

O

O

O

O

C

R

N

2 2 + 2HCHO 2 1 2

1 2 2

CH3

CH3CH3

CH3

CH3 CH3

H3C

(2M)

Cu(II) salt + NaX

(X = OAc OBz)

L1 and L2

L1-R = CH3

L2-R = C2H5

Cu

R1

R = CH3 C2H5

X = ClClO4

R = CH3 C2H5

R1 = CH3 C6H5

CH3

CH3

CH3 CH3

2 1

+ RndashNH





2CO3 A


3200MHzTMS) 120575 = 157 203 (ndashCH

3)





3) 252 (br 16H and


29H45N5O2() C 703 H 91 N 141

Found C 701 H 92 N 142


3200MHzTMS) 120575 = 73 (ali-CH

3) 156 and

158 (N-CH3and N-CH

2) 203 (Ar-CH

3) 406 546 552


390MHzTMS) 120575 = 113 (t 3H and CH

3of ethyl


3)



30H47N5O2() C 707 H 92 N 138

Found C 707 H 92 N 137



31H50ClCu2N5O10





2L1 (OAc)]ClO

4sdot2H2O




Found C 496 H 61 Cu 143 N 77


29H47Cl2Cu2N5O4





Found C 406 H 54 Cu 148 N 813


30H49Cl2Cu2N5O12() C 414 H 56









248 (19 500)


246 (19 700)


242 (18 600)


248 (17 200)

5 [Cu2L1Cl2]sdot2H2O 650 (290) 420 (1310) 284 (14 100)

244 (19 800)

6 [Cu2L2Cl2]sdot2H2O 638 (249) 412 (540) 286 (12 500)

238 (13 000)

7 [Cu2L1(ClO4)2]sdot2H2O 657 (208) 405 (sh) 287 (14 700)

235 (16 300)8

[Cu2L2(ClO4)2]sdot2H2O 658 (192) 410 (sh) 285 (13 300)



No Complexes 119864

1 pcv 119864

1 pav 119864

1

12v

(Δ119864mv) 119864

2 pcv 119864

2 pav 119864

2

12V

(Δ119864mv)1 [Cu2L











119901119888) anodic


119901) and redox

potential 11986412




eminus999445999468 Cu (I)Cu (I) (1)




No Complexes 120583


119892

119892

perp










30120583A

Curr

ent



(a)



25120583A

Curr

ent

(b)



2L2(ClO

4)2]sdot2H2O (6)





120594

119898= (

119873119892

2120573

2

3119896119879

) [3 + exp(minus2 J119896119879

)]

minus1

(1 minus 119901) +

045119901

119879

+ 119873

120572

(3)

where 120594119898






= 217ndash223 and 119892

perp=



0 100 200 300 40005

10

15

20

05

10

15

20

Temperature (K)

120583eff

(BmiddotM

)

120594m

(times103

cm3

Mminus1)


2L1(OAc)]ClO

4sdot2H2Osdot (1)


(a)

(b)

200G



2L2(ClO

4)2]sdot2H2O (8)


4 Conclusion




2and in d




2ndash





Acknowledgment


References





































2] and [Cu

4] headgroups









2O2andN(amine)












Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of


OH OH OH

N

R

OH OH

N

R

N

NN

N

PC


Cu(II) salt

N NR

O

O

N

Cu

Cu

XX

N

N

CuN

N

N

N

O

O

O

O

C

R

N

2 2 + 2HCHO 2 1 2

1 2 2

CH3

CH3CH3

CH3

CH3 CH3

H3C

(2M)

Cu(II) salt + NaX

(X = OAc OBz)

L1 and L2

L1-R = CH3

L2-R = C2H5

Cu

R1

R = CH3 C2H5

X = ClClO4

R = CH3 C2H5

R1 = CH3 C6H5

CH3

CH3

CH3 CH3

2 1

+ RndashNH





2CO3 A


3200MHzTMS) 120575 = 157 203 (ndashCH

3)





3) 252 (br 16H and


29H45N5O2() C 703 H 91 N 141

Found C 701 H 92 N 142


3200MHzTMS) 120575 = 73 (ali-CH

3) 156 and

158 (N-CH3and N-CH

2) 203 (Ar-CH

3) 406 546 552


390MHzTMS) 120575 = 113 (t 3H and CH

3of ethyl


3)



30H47N5O2() C 707 H 92 N 138

Found C 707 H 92 N 137



31H50ClCu2N5O10





2L1 (OAc)]ClO

4sdot2H2O




Found C 496 H 61 Cu 143 N 77


29H47Cl2Cu2N5O4





Found C 406 H 54 Cu 148 N 813


30H49Cl2Cu2N5O12() C 414 H 56









248 (19 500)


246 (19 700)


242 (18 600)


248 (17 200)

5 [Cu2L1Cl2]sdot2H2O 650 (290) 420 (1310) 284 (14 100)

244 (19 800)

6 [Cu2L2Cl2]sdot2H2O 638 (249) 412 (540) 286 (12 500)

238 (13 000)

7 [Cu2L1(ClO4)2]sdot2H2O 657 (208) 405 (sh) 287 (14 700)

235 (16 300)8

[Cu2L2(ClO4)2]sdot2H2O 658 (192) 410 (sh) 285 (13 300)



No Complexes 119864

1 pcv 119864

1 pav 119864

1

12v

(Δ119864mv) 119864

2 pcv 119864

2 pav 119864

2

12V

(Δ119864mv)1 [Cu2L











119901119888) anodic


119901) and redox

potential 11986412




eminus999445999468 Cu (I)Cu (I) (1)




No Complexes 120583


119892

119892

perp










30120583A

Curr

ent



(a)



25120583A

Curr

ent

(b)



2L2(ClO

4)2]sdot2H2O (6)





120594

119898= (

119873119892

2120573

2

3119896119879

) [3 + exp(minus2 J119896119879

)]

minus1

(1 minus 119901) +

045119901

119879

+ 119873

120572

(3)

where 120594119898






= 217ndash223 and 119892

perp=



0 100 200 300 40005

10

15

20

05

10

15

20

Temperature (K)

120583eff

(BmiddotM

)

120594m

(times103

cm3

Mminus1)


2L1(OAc)]ClO

4sdot2H2Osdot (1)


(a)

(b)

200G



2L2(ClO

4)2]sdot2H2O (8)


4 Conclusion




2and in d




2ndash





Acknowledgment


References





































2] and [Cu

4] headgroups









2O2andN(amine)












Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of




3) 252 (br 16H and


29H45N5O2() C 703 H 91 N 141

Found C 701 H 92 N 142


3200MHzTMS) 120575 = 73 (ali-CH

3) 156 and

158 (N-CH3and N-CH

2) 203 (Ar-CH

3) 406 546 552


390MHzTMS) 120575 = 113 (t 3H and CH

3of ethyl


3)



30H47N5O2() C 707 H 92 N 138

Found C 707 H 92 N 137



31H50ClCu2N5O10





2L1 (OAc)]ClO

4sdot2H2O




Found C 496 H 61 Cu 143 N 77


29H47Cl2Cu2N5O4





Found C 406 H 54 Cu 148 N 813


30H49Cl2Cu2N5O12() C 414 H 56









248 (19 500)


246 (19 700)


242 (18 600)


248 (17 200)

5 [Cu2L1Cl2]sdot2H2O 650 (290) 420 (1310) 284 (14 100)

244 (19 800)

6 [Cu2L2Cl2]sdot2H2O 638 (249) 412 (540) 286 (12 500)

238 (13 000)

7 [Cu2L1(ClO4)2]sdot2H2O 657 (208) 405 (sh) 287 (14 700)

235 (16 300)8

[Cu2L2(ClO4)2]sdot2H2O 658 (192) 410 (sh) 285 (13 300)



No Complexes 119864

1 pcv 119864

1 pav 119864

1

12v

(Δ119864mv) 119864

2 pcv 119864

2 pav 119864

2

12V

(Δ119864mv)1 [Cu2L











119901119888) anodic


119901) and redox

potential 11986412




eminus999445999468 Cu (I)Cu (I) (1)




No Complexes 120583


119892

119892

perp










30120583A

Curr

ent



(a)



25120583A

Curr

ent

(b)



2L2(ClO

4)2]sdot2H2O (6)





120594

119898= (

119873119892

2120573

2

3119896119879

) [3 + exp(minus2 J119896119879

)]

minus1

(1 minus 119901) +

045119901

119879

+ 119873

120572

(3)

where 120594119898






= 217ndash223 and 119892

perp=



0 100 200 300 40005

10

15

20

05

10

15

20

Temperature (K)

120583eff

(BmiddotM

)

120594m

(times103

cm3

Mminus1)


2L1(OAc)]ClO

4sdot2H2Osdot (1)


(a)

(b)

200G



2L2(ClO

4)2]sdot2H2O (8)


4 Conclusion




2and in d




2ndash





Acknowledgment


References





































2] and [Cu

4] headgroups









2O2andN(amine)












Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of





248 (19 500)


246 (19 700)


242 (18 600)


248 (17 200)

5 [Cu2L1Cl2]sdot2H2O 650 (290) 420 (1310) 284 (14 100)

244 (19 800)

6 [Cu2L2Cl2]sdot2H2O 638 (249) 412 (540) 286 (12 500)

238 (13 000)

7 [Cu2L1(ClO4)2]sdot2H2O 657 (208) 405 (sh) 287 (14 700)

235 (16 300)8

[Cu2L2(ClO4)2]sdot2H2O 658 (192) 410 (sh) 285 (13 300)



No Complexes 119864

1 pcv 119864

1 pav 119864

1

12v

(Δ119864mv) 119864

2 pcv 119864

2 pav 119864

2

12V

(Δ119864mv)1 [Cu2L











119901119888) anodic


119901) and redox

potential 11986412




eminus999445999468 Cu (I)Cu (I) (1)




No Complexes 120583


119892

119892

perp










30120583A

Curr

ent



(a)



25120583A

Curr

ent

(b)



2L2(ClO

4)2]sdot2H2O (6)





120594

119898= (

119873119892

2120573

2

3119896119879

) [3 + exp(minus2 J119896119879

)]

minus1

(1 minus 119901) +

045119901

119879

+ 119873

120572

(3)

where 120594119898






= 217ndash223 and 119892

perp=



0 100 200 300 40005

10

15

20

05

10

15

20

Temperature (K)

120583eff

(BmiddotM

)

120594m

(times103

cm3

Mminus1)


2L1(OAc)]ClO

4sdot2H2Osdot (1)


(a)

(b)

200G



2L2(ClO

4)2]sdot2H2O (8)


4 Conclusion




2and in d




2ndash





Acknowledgment


References





































2] and [Cu

4] headgroups









2O2andN(amine)












Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of



No Complexes 120583


119892

119892

perp










30120583A

Curr

ent



(a)



25120583A

Curr

ent

(b)



2L2(ClO

4)2]sdot2H2O (6)





120594

119898= (

119873119892

2120573

2

3119896119879

) [3 + exp(minus2 J119896119879

)]

minus1

(1 minus 119901) +

045119901

119879

+ 119873

120572

(3)

where 120594119898






= 217ndash223 and 119892

perp=



0 100 200 300 40005

10

15

20

05

10

15

20

Temperature (K)

120583eff

(BmiddotM

)

120594m

(times103

cm3

Mminus1)


2L1(OAc)]ClO

4sdot2H2Osdot (1)


(a)

(b)

200G



2L2(ClO

4)2]sdot2H2O (8)


4 Conclusion




2and in d




2ndash





Acknowledgment


References





































2] and [Cu

4] headgroups









2O2andN(amine)












Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of


0 100 200 300 40005

10

15

20

05

10

15

20

Temperature (K)

120583eff

(BmiddotM

)

120594m

(times103

cm3

Mminus1)


2L1(OAc)]ClO

4sdot2H2Osdot (1)


(a)

(b)

200G



2L2(ClO

4)2]sdot2H2O (8)


4 Conclusion




2and in d




2ndash





Acknowledgment


References





































2] and [Cu

4] headgroups









2O2andN(amine)












Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of




























2] and [Cu

4] headgroups









2O2andN(amine)












Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of




2O2andN(amine)












Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of










Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of

research article synthesis and characterisation of new...

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