research article synthesis and characterization of the...

Hindawi Publishing CorporationInternational Journal of Inorganic ChemistryVolume 2013 Article ID 502856 4 pageshttpdxdoiorg1011552013502856

Research ArticleSynthesis and Characterization ofthe Adducts of Bis(O-ethyldithiocarbonato)copper(II)with Substituted Pyridines

Gurpreet Kour Inderjeet Kour and Renu Sachar

Department of Chemistry University of Jammu Babasaheb Ambedkar Road Jammu Tawi Jammu 180006 India

Correspondence should be addressed to Gurpreet Kour gurpreetkour94yahoocom

Received 22 August 2013 Revised 29 October 2013 Accepted 12 November 2013

Academic Editor Alfonso Castineiras

Copyright copy 2013 Gurpreet Kour et al This is an open access article distributed under the Creative Commons Attribution Licensewhich permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited

Monomeric five coordinated adducts of bis(O-ethyldithiocarbonato)copper(II) of general formula [Cu(C2H5OCS2)2(L)] [L = 2-

3- 4-methylpyridines and 2- 3- 4-ethylpyridines] have been synthesized and characterized by elemental analysis ir and electronicspectroscopy magnetic and conductivity measurements Analytical results show that the adducts have 1 1 stoichiometry Theadducts were found to be paramagnetic and their magnetic moments at room temperature lie within the 181ndash194 BM range andthis indicates the presence of one unpaired electron All the adducts have distorted square pyramidal geometry

1 Introduction

O-Alkyldithiocarbonates popularly known as xanthatesderivatives have found a wide pra ctical application asaddition to lubricating oils antioxidants for polyolefins andso forth However alkylxanthates aremainly used in flotationconcentration of nonferrous metal sulfide ores These areextensively used as pharmaceuticals fungicides pesticidesand quite recently in therapy for HIV infections [1ndash3]Divalent transition metals xanthates are partly unsaturatedand can therefore form 1 1 adducts with electron donors suchas neutral nitrogen oxygen phosphorus or sulfur donorsin which the coordination geometry ranges from squarepyramidal to trigonal bipyramidal [4] Such adducts of manytransition metals such as Ni Zn Mn V Pt and Pd are wellstudied but little attention has been paid to the xanthates ofcopper owing to their instability Here we report synthesisand investigation of the 1 1 adducts of some adducts ofcopper(II)xanthates with substituted pyridines such as 2- 3-4-methylpyridines and 2- 3- 4-ethylpyridines

2 Experimental

21 Preparation of Potassium Salt of O-ethyldithiocarbonatePotassium salt of ethyl xanthate was prepared by the method

reported in literature [5] Into a 500mL round bottomedflask fitted with a reflux condenser was placed 075 moleof potassium hydroxide pellets and 120 g of ethanol Thereaction mixture was heated under reflux for 1 hour Themixture was then cooled and liquid from the residual solidwas decanted off into another dry 500mL flask To thisflask was added 45mL (075 mole) of carbon disulfide slowlywith constant shaking The residual solid yellow mass wasfiltered (after cooling in ice) on a sintered glass funnel atthe pump It was washed with three 25mL portions of etherThe resulting potassium salt of ethyl xanthate was dried ina vacuum desiccator over anhydrous calcium chloride Theyield was about 75 g It was then recrystallized from ether

22 Preparation of Adducts of Bis(O-ethyldithiocarbon-ato)copper(II) with Substituted Pyridines The yellowcoloured parent compound copper(II)xanthate could notbe isolated because it changed rapidly into brown colouredcopper(I)xanthate The addition complexes were preparedby the direct reaction of solution of metal salt solution ofpotassium salt of ethylxanthate and substituted pyridineAbout 20mL solution of cupric chloride dihydrate (00025mole) in acetone was prepared To this solution a solution ofpotassium salt of ethyl xanthate (0005 mole) and substituted

2 International Journal of Inorganic Chemistry

N

X

CuS

S

S

S

C

N

X

AcetoneC2H5O COC2H5

CuCl2H2O + C2H5OCS2K +

Scheme 1 Scheme of the proposed structure where X= CH3C2H5

Table 1Molar conductancemagneticmoments and analytical data of 1 1 adducts of bis(119874-ethyldithiocarbonato)copper(II) with substitutedpyridines

S No Name of the compound Molar conductance(ohmminus1 molminus1 cm2)

120583eff (BM)at 293K

found calculatedC H N S C H N S

1 Bis(ethylxanthato)(2-methylpyridine)copper(II) 349 188 330 302 30 327 344 391 364 3332 Bis(ethylxanthato)(3-methylpyridine)copper(II) 385 192 348 398 278 319 362 427 351 3223 Bis(ethylxanthato)(4-methylpyridine)copper(II) 435 193 355 355 298 308 362 427 351 3224 Bis(ethylxanthato)(2-ethylpyridine)copper(II) 389 176 366 401 315 307 379 461 340 3115 Bis(ethylxanthato)(3-ethylpyridine)copper(II) 397 182 362 400 332 306 379 461 340 3116 Bis(ethylxanthato)(4-ethylpyridine)copper(II) 474 185 366 398 320 302 379 461 340 311

pyridine (00025 mole) [2-methylpyridine = 0235 g 3-methylpyridine = 0235 g 4-methylpyridine = 0235 g2-ethylpyridine = 027 g and 3-ethylpyridine = 027 g4-ethylpyridine = 027 g] prepared in 50mL of acetone wasadded slowly with constant stirring Dark green colouredprecipitates so obtained were filtered washed with acetoneand dried over anhydrous calcium chloride in a vacuumdesiccator at room temperature A scheme of the proposedstructure is shown in Scheme 1

3 Results and Discussion

The addition complexes of bis(O-ethyldithiocarbon-ato)copper(II) are microcrystalline solids which are lightgreen in colour These are insoluble in common organicsolvents such as ethanol acetone and benzene Howeverthese are soluble in dimethylformamide and dimethy-lsulfoxide On the basis of elemental analysis (Table 1) theyhave been assigned the general formula Cu(S

2COC2H5)2L [L

= 2- 3- 4-methyl and 2- 3- 4-ethyl-pyridines] Conductancevalues of these complexes in DMF fall in the range of 350ndash500 ohmminus1moleminus1 cm2 (Table 1) These values are lowerthan the values expected for any uni-univalent electrolytesin this solvent suggesting that these complexes are neutraland nonionic in character [6 7] The magnetic momentsof 1 1 complexes of bis(O-ethyldithiocarbonato)copper(II)with substituted pyridines fall in the range 181ndash194 BM(Table 1) which is in agreement with magnetic momentvalues observed for distorted square pyramidal complexes ofcopper(II) [8ndash10]

Free dithiocarbonate shows vibrations due to CndashOndashCstretching in the range of 1270ndash1280 cmminus1 and the CndashS

stretching vibration appears as two bands in the range of1057ndash1070 cmminus1 In the present work a single sharp bandof high intensity has been observed in all the complexes inthe range of 1011ndash1035 cmminus1 (Table 2) The appearance of theonly CndashS band suggests symmetrical bidentate binding ofthe dithiocarbonate moiety There is a positive shift of 10ndash30 cmminus1 in comparison to the free ligands This indicatesthat the dithiocarbonate ligand coordinates with the metalthrough sulfur atoms Moreover the complexes show a bandin the region 1190ndash1220 cmminus1 which is attributed to ] (CndashO)of dithiocarbonate moiety In these complexes CndashH out ofplane bands occur at lower energy positions on complexationindicating red shifts which confirm that these ligands inter-act with the metal ion through their respective ring nitrogenatom A new band of medium to strong intensity observed inthe range of 320ndash352 cmminus1 may be attributed toCundashS stretch-ing mode [11] The electronic spectra of 1 1 addition com-plexes of bis(O-ethyldithiocarbonato)copper(II) have beenrecorded in DMF The copper(II) five coordinate complexesare expected to show a strong broad band appearing inthe region 12000ndash17500 cmminus1 (Table 2) The band maximumappears around 16000 cmminus1 and is assigned to 119889

119909119911 119889119910119911rarr

1198891199092-1199102 transition A weak shoulder is associated with it due

to 1198891199112 rarr 119889

1199092-1199102 transition Third possible transition is

orbitally forbidden and merges with the broad band Therelative energy order of these transitions depends upon theextent of axial ligand-metal interaction

The complexes under observation show an intense bandin the range of 15500ndash17500 cmminus1 which is attributed to d-d transitions as observed in most of the copper complexes(]1) This main absorption band around 16000 cmminus1 can be

assigned to 119889119909119911 119889119910119911rarr 1198891199092-1199102 (Table 2) The appearance of

International Journal of Inorganic Chemistry 3

Table 2 Electronic and vibrational spectral data of 1 1 adducts of bis(119874-ethyldithiocarbonato)copper(II) with substituted pyridines

S No Name of the adduct Yield and (melting point) ]1(cmminus1) ] (CndashS) ] (CndashO) ] (CundashS)

1 Bis(ethylxanthato)(2-methylpyridine)copper(II) 62 (89∘C) 16421 1012 1199 3242 Bis(ethylxanthato)(3-methylpyridine)copper(II) 68 (87∘C) 16623 1022 1210 3353 Bis(ethylxanthato)(4-methylpyridine)copper(II) 70 (885∘C) 16858 1032 1200 3304 Bis(ethylxanthato)(2-ethylpyridine)copper(II) 65 (862∘C) 16990 1020 1202 3275 Bis(ethylxanthato)(3-ethylpyridine)copper(II) 68 (868∘C) 16400 1034 1198 3246 Bis(ethylxanthato)(4-ethylpyridine)copper(II) 69 (874∘C) 15890 1037 1200 338

19000 4000 6000 8000

0010

2505

3752

5000

Abs

Wavelength (nm)

Electronic spectra of the complexes∙ Instrument performance

Model UV-VIS spectrophotometer

Number 18-1901-01-0103

Spectral bandwidth 200 nm

∙ Scan spectrum performance

Scan range 19000 to 80000 nm

Measure mode Abs

Interval 100 nm

Speed fast

Data file i7spd

Create datetime Thursday September 12 2013 121047 PM

Data type originalMethod file

∙ Analyse noteAnalyser administratorSample name

(a)

19000 4000 6000 8000

0010

2505

3752

5000

Abs

Wavelength (nm)

∙ Instrument performanceModel UV-VIS spectrophotometerNumber 18-1901-01-0103Spectral bandwidth 200 nm



Measure mode Abs

Interval 100 nm

Speed fast

Data file shenglspd

Create datetime Thursday September 12 2013 12120728 PMData type originalMethod file


(b)

Figure 1


one bandwith the intensity pattern suggests square pyramidalgeometry around copper(II) ion in these 1 1 adducts [12]Figure 1

4 Conclusion

The results obtained from various physicochemical andspectral techniques suggest that the adducts of bis(O-ethyld-ithiocarbonato)copper(II) with substituted pyridines have1 1 stoichiometry with square pyramidal geometry aroundcopper(II) ion

References

[1] J J Santanaa andRM SoutoHonolulu PRiME the Electrochem-ical Society 2012

[2] W Mellert E Amtmann V Erfle and G Sauer ldquoInhibition ofHIV-1 replication by an antiviral xanthate compound in vitrordquoAIDS Research and Human Retroviruses vol 4 no 1 pp 71ndash811988

[3] G R R Behbehani M Mehreshtiagh and L B A A SabouryldquoA calorimetric investigation for the bindings of mushroomtyrosinase to p-phenylene-bis dithiocarbamate and xanthatesrdquoJournal of the Serbian Chemical Society vol 78 no 2 pp 255ndash263 2013

[4] A O Gorgulu H Celikkan and M Arslan ldquoThe synthesischaracterization and electrochemical behavior of transitionmetal complexes containing nitrogen heterocyclic sulphurdonor ligandActa Chimica Slovenicardquo vol 56 pp 334ndash3392009

[5] B S Furniss A J Hannaford P W G Smith and A RTatchell Vogelrsquos Text Book of Practical Organic ChemistryPearson Education London UK 5th edition 1989

[6] R L Martin and A Whitley ldquoMagnetic studies with copper(II)salts Part III The constitution of copper(II)n-alkanoates insolutionrdquo Journal of the Chemical Society vol 13 pp 1394ndash14021958

[7] W J Geary ldquoThe use of conductivity measurements in organicsolvents for the characterisation of coordination compoundsrdquoCoordination Chemistry Reviews vol 7 no 1 pp 81ndash122 1971

[8] R A Ahmadi F Hasanvand G Bruno H A Rudbari andS Amani ldquoSynthesis spectroscopy and magnetic characteriza-tion of Copper(II) and Cobalt(II) complexes with 2-Amino-5-bromopyridine as ligandrdquo ISRN Inorganic Chemistry vol 2013Article ID 426712 7 pages 2013

[9] L Singh D K Sharma U Singh and A Kumar ldquoSynthesisand spectral studies of Cu(II) coordination compounds of4[N-(cinnamalidene) amino] antipyrine semicarbazonerdquoAsianJournal of Chemistry vol 16 no 2 pp 577ndash580 2004

[10] N H Al-Shaalan ldquoSynthesis characterization and biologicalactivities of Cu(II) Co(II) Mn(II) Fe(II) and UO2(VI)complexes with a new Schiff base hydrazone O-hydrox-yacetophenone-7-chloro-4-quinoline hydrazonerdquo Moleculesvol 16 no 10 pp 8629ndash8645 2011

[11] N Singh and A Parsad ldquoSynthesis characterization and elec-trical conductivities of mixed-ligand (N SSe) heterobimetalliccoordination polymers and their I

2-doped productsrdquo Indian

Journal of Chemistry A vol 47 pp 650ndash656 2008[12] M Zhou L Sonq and K Shu ldquoA square-pyramidal copper(II)

complex with strong intramolecular hydrogen bonds

diaqua(NN1015840-dimethylformamide-120581O)bis[2-(diphenylphos-phoryl)benzoato-120581O]copper(II)rdquoActa Crystallographica C vol69 pp 463ndash466 2013

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


N

X

CuS

S

S

S

C

N

X

AcetoneC2H5O COC2H5

CuCl2H2O + C2H5OCS2K +

Scheme 1 Scheme of the proposed structure where X= CH3C2H5

Table 1Molar conductancemagneticmoments and analytical data of 1 1 adducts of bis(119874-ethyldithiocarbonato)copper(II) with substitutedpyridines

S No Name of the compound Molar conductance(ohmminus1 molminus1 cm2)

120583eff (BM)at 293K

found calculatedC H N S C H N S

1 Bis(ethylxanthato)(2-methylpyridine)copper(II) 349 188 330 302 30 327 344 391 364 3332 Bis(ethylxanthato)(3-methylpyridine)copper(II) 385 192 348 398 278 319 362 427 351 3223 Bis(ethylxanthato)(4-methylpyridine)copper(II) 435 193 355 355 298 308 362 427 351 3224 Bis(ethylxanthato)(2-ethylpyridine)copper(II) 389 176 366 401 315 307 379 461 340 3115 Bis(ethylxanthato)(3-ethylpyridine)copper(II) 397 182 362 400 332 306 379 461 340 3116 Bis(ethylxanthato)(4-ethylpyridine)copper(II) 474 185 366 398 320 302 379 461 340 311

pyridine (00025 mole) [2-methylpyridine = 0235 g 3-methylpyridine = 0235 g 4-methylpyridine = 0235 g2-ethylpyridine = 027 g and 3-ethylpyridine = 027 g4-ethylpyridine = 027 g] prepared in 50mL of acetone wasadded slowly with constant stirring Dark green colouredprecipitates so obtained were filtered washed with acetoneand dried over anhydrous calcium chloride in a vacuumdesiccator at room temperature A scheme of the proposedstructure is shown in Scheme 1

3 Results and Discussion

The addition complexes of bis(O-ethyldithiocarbon-ato)copper(II) are microcrystalline solids which are lightgreen in colour These are insoluble in common organicsolvents such as ethanol acetone and benzene Howeverthese are soluble in dimethylformamide and dimethy-lsulfoxide On the basis of elemental analysis (Table 1) theyhave been assigned the general formula Cu(S

2COC2H5)2L [L

= 2- 3- 4-methyl and 2- 3- 4-ethyl-pyridines] Conductancevalues of these complexes in DMF fall in the range of 350ndash500 ohmminus1moleminus1 cm2 (Table 1) These values are lowerthan the values expected for any uni-univalent electrolytesin this solvent suggesting that these complexes are neutraland nonionic in character [6 7] The magnetic momentsof 1 1 complexes of bis(O-ethyldithiocarbonato)copper(II)with substituted pyridines fall in the range 181ndash194 BM(Table 1) which is in agreement with magnetic momentvalues observed for distorted square pyramidal complexes ofcopper(II) [8ndash10]

Free dithiocarbonate shows vibrations due to CndashOndashCstretching in the range of 1270ndash1280 cmminus1 and the CndashS

stretching vibration appears as two bands in the range of1057ndash1070 cmminus1 In the present work a single sharp bandof high intensity has been observed in all the complexes inthe range of 1011ndash1035 cmminus1 (Table 2) The appearance of theonly CndashS band suggests symmetrical bidentate binding ofthe dithiocarbonate moiety There is a positive shift of 10ndash30 cmminus1 in comparison to the free ligands This indicatesthat the dithiocarbonate ligand coordinates with the metalthrough sulfur atoms Moreover the complexes show a bandin the region 1190ndash1220 cmminus1 which is attributed to ] (CndashO)of dithiocarbonate moiety In these complexes CndashH out ofplane bands occur at lower energy positions on complexationindicating red shifts which confirm that these ligands inter-act with the metal ion through their respective ring nitrogenatom A new band of medium to strong intensity observed inthe range of 320ndash352 cmminus1 may be attributed toCundashS stretch-ing mode [11] The electronic spectra of 1 1 addition com-plexes of bis(O-ethyldithiocarbonato)copper(II) have beenrecorded in DMF The copper(II) five coordinate complexesare expected to show a strong broad band appearing inthe region 12000ndash17500 cmminus1 (Table 2) The band maximumappears around 16000 cmminus1 and is assigned to 119889

119909119911 119889119910119911rarr

1198891199092-1199102 transition A weak shoulder is associated with it due

to 1198891199112 rarr 119889

1199092-1199102 transition Third possible transition is

orbitally forbidden and merges with the broad band Therelative energy order of these transitions depends upon theextent of axial ligand-metal interaction

The complexes under observation show an intense bandin the range of 15500ndash17500 cmminus1 which is attributed to d-d transitions as observed in most of the copper complexes(]1) This main absorption band around 16000 cmminus1 can be

assigned to 119889119909119911 119889119910119911rarr 1198891199092-1199102 (Table 2) The appearance of





19000 4000 6000 8000

0010

2505

3752

5000

Abs

Wavelength (nm)



Number 18-1901-01-0103




Measure mode Abs

Interval 100 nm

Speed fast

Data file i7spd




(a)

19000 4000 6000 8000

0010

2505

3752

5000

Abs

Wavelength (nm)




Measure mode Abs

Interval 100 nm

Speed fast

Data file shenglspd



(b)

Figure 1



4 Conclusion


References

























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of





19000 4000 6000 8000

0010

2505

3752

5000

Abs

Wavelength (nm)



Number 18-1901-01-0103




Measure mode Abs

Interval 100 nm

Speed fast

Data file i7spd




(a)

19000 4000 6000 8000

0010

2505

3752

5000

Abs

Wavelength (nm)




Measure mode Abs

Interval 100 nm

Speed fast

Data file shenglspd



(b)

Figure 1



4 Conclusion


References

























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of



4 Conclusion


References

























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 characterization of the...

Documents