Synthesis and Characterization of bis(2-hydroxyethyl)dithiocarbamate complexes of Zinc, Mercury, Uranium, Lead, Chromium, and Calcium Gregory Trzcinski.

Synthesis and Characterization of bis(2-hydroxyethyl)dithiocarbamate

complexes of Zinc, Mercury, Uranium, Lead, Chromium, and

Calcium

Gregory Trzcinski

Department of Chemistry

McDaniel College

February 27, 2009

Overview• Introduction

– Why this ligand?– Why these metals?

• Facts on metals– What type of analyses?

– “The Big Nine”• Syntheses

– Ligand• Proposed Mechanism

– Metal complexes• Self Assembly

• Results/Discussion– “The Big Nine”

• Conclusion • Future Work• Questions?

Why this ligand?

• Increased interest– Analytical agents

– Medicinal drugs

• Known treatment for heavy metal and organometallic cation poisoning

• Known metal binding capacities

Potassium bis(2-hydroxyethyl)dithiocarbamate

Why these metals?

• Interested in the metals• Recognized toxicity in sufficient amounts• Availability

– In the environment– In reagents

• More complete study of Zinc and Mercury started by Pages et al.

Calcium• Essential• Most abundant metal in the

body• Body needs a constant level

– Muscle contractions

• Daily recommended amount ~1000mg

• Excess can lead to health concerns– Decreased absorption of

other metals  http://product-image.tradeindia.com/00063632/b/Calcium-Chloride-Anhydrous-Powder.jpg

Chromium

• Essential in trace amounts

• Adequate intake ~35μg

• Found in two forms 3+, biologically active, and 6+, toxic

• Few adverse effectshttp://ankomreactive.ru/kalii

Zinc

• Essential

• Variety of cellular functions

• Adequate intake ~11mg

• Excess can lead to health concerns– Decrease of HDL

• Toxicity has led to deficiencies in other essential metals http://en.wikipedia.org/wiki/Zinc_chloride

Mercury

• Non-essential, toxic• Vaporizes at ambient

temperature and pressure

• Vaporized form can remain in the air for up to a year

• Deposited all over the world

http://img.alibaba.com/photo/104416972/Mercuric_Chloride.summ.jpg

Uranium

• Non-essential

• Used in power plants

• Depleted uranium most common– Byproduct

– Military use

• 90μg is present in body

• Increased use can be hazardous

http://en.wikipedia.org/wiki/Uranyl_acetate

Lead

• Non-essential• Very toxic• Typically found in

paint• More readily absorbed

by children• Myriad of health

concernshttp://www.alibaba.com/product/chemarea-12251525-10992269/Lead_Acetate.html

“The Big Nine”• Melting Point (in Celsius)

• Yield (in grams)

• Percent Yield

• 1H Nuclear Magnetic Resonance spectroscopy (NMR)

• 13C NMR

• Infrared Spectroscopy (IR)

• Ultraviolet-Visible Spectrophotometry (UV-Vis)

• Mass Spectrometry (Mass Spec): Electrospray + or -

• Elemental Analysis

What to look for and accomplish?• The presence of the

metal in the resultant complexes

• Theorize a structure for each complex

N

C

S

S

HO

OH

N

C

S

S

OH

HO

Pb

N

S

S

OH

OH

N

S

S

HO

OH

N

S

S

OH

HO

U

O

O

K

Ligand Synthesis

CS2

DEA

KOH

K[bhedtc]

3.

1. 2.

Proposed Mechanism

Complex Syntheses

K[bhedtc] in H2O

CaCl2 in EtOH HgCl2 in MeOH ZnCl2 in H2O

M[bhedtc]2

M = Ca, Hg, Zn

Complex Syntheses

K[UO2(bhedtc)3] Pb[bhedtc]2

UO2(OAc)2· 2H2O in H2O

Cr[bhedtc]3

K2Cr2O7 in H2OPb(OAc)2 · 3H2O

in H2O

K[bhedtc] in H2O

Self Assembly

M[bhedtc]2

MCl2

DEA

CS2 in MeOH

M = Hg or Zn

1.

3.

2.

Solubility Chart

Complexes H2O MeOH EtOH Acetonitrile DMSO Acetone CHCl3 DMF

K[bhedtc] vs i i i s i i i

Ca[bhedtc]2 sl i i i sl i i i

Cr[bhedtc]3 i i i i i i i i

Hg[bhedtc]2 i i i i s i i

sl -transpare

nt gray

Pb[bhedtc]2 i i i i s i i s

K[UO2(bhedtc)3] s-orange sl-light orange i i s-orange i i s-yellow

Zn[bhedtc]2 i s i i s i i s

Data Chart

K[bhedtc] 1H NMR in DMSO

3.638

4.100

4.777

Zn[bhedtc]2 1H NMR in DMSO

Down: 0.149

Up: 0.163

Down: 0.084

Hg[bhedtc]2 1H NMR in DMSO

Down: 0.234

Up: 0.220

Down: 0.108

Pb[bhedtc]2 1H NMR in DMSO

Down: 0.134

Up: 0.208

Down: 0.095

K[bhedtc] 13C NMR in DMSO

13C NMR results

Complexes C1 C2 C3 Other K[bhedtc]_ 227.272 72.947 75.227 ~ K[bhedtc] 214.647 55.655 59.343 59.502

Ca[bhedtc] 2 ~ ~ ~ ~

Cr[bhedtc] 3 ~ ~ ~ ~

Hg[bhedtc] 2 202.183 57.692 59.954 ~

Pb[bhedtc] 2 204.118 55.871 58.015 ~

K[UO2( bhedtc) 3] 204.225 54.828 58.383 206.922

Zn[bhedtc] 2 204.171 57.893 57.985 ~

Carbon NMR Peaks*

*DMSO used as solvent; Chemical shifts downfield of TMS_ D20 used as solvent; Chemical shifts downfield of TMS

N

C

H2C

H2C

H2C

HO

S

S

H2C

HO

1

23

2

3

K[bhedtc] IR

K[bhedtc] as KBr disc

15

16

17

18

1920

21

22

23

24

25

450950145019502450295034503950

Wavenumber (1/ cm)

%T

Ca[bhedtc]2 over K[bhedtc]K[bhedtc] and Ca[bhedtc]2

(Synthesized with CaCl2 in EtOH) as KBr discs

10

15

20

25

30

35

450145024503450

Wavenumber (1/ cm)

% T

Ca[bhedtc]2 K[bhedtc]

Cr[bhedtc]3 over K[bhedtc]

K[bhedtc] and Cr[bhedtc]3 as KBr discs

10

15

20

25

450145024503450

Wavenumber (1/ cm)

% T

Cr[bhedtc]3 K[bhedtc]

Zn[bhedtc]2 over K[bhedtc]

K[bhedtc] and Zn[bhedtc]2 as KBr discs

15

20

25

30

35

450145024503450

Wavenumber (1/ cm)

% T

Zn[bhedtc]2 K[bhedtc]

Hg[bhedtc]2 over K[bhedtc]

K[bhedtc] and Hg[bhedtc]2 as KBr discs

10

15

20

25

30

35

450145024503450Wavenumber (1/ cm)

% T

Hg[bhedtc]2 K[bhedtc]

K[UO2(bhedtc)3] over K[bhedtc]

K[bhedtc] and K[UO2(bhedtc)3] as KBr discs

15

20

25

30

35

450145024503450Wavenumber (1/ cm)

% T

K[UO2(bhedtc)3] K[bhedtc]

Pb[bhedtc]2 over K[bhedtc]

K[bhedtc] and Pb[bhedtc]2 as KBr discs

15

20

25

30

35

450145024503450

Wavenumber (1/ cm)

% T

Pb[bhedtc]2 K[bhedtc]

UV-VisComplexes Solvent Concentration (M) Absorbance Epsilon (Au*L)/(cm*mol)K[bhedtc] H2O 2.73E-05 0.1006 3.68E+03 K[bhedtc] DMSO 2.28E-05 0.1331 5.84E+03

2.28E-05 0.1197 5.25E+03Ca[bhedtc]2 H2O 1.02E-04 0.8935 8.76E+03

1.02E-04 0.885 8.68E+031.02E-04 0.6861 6.73E+03

Cr[bhedtc]3 N/A N/A N/A N/AHg[bhedtc]2 DMSO 9.80E-06 0.1575 1.61E+04

9.80E-06 0.0778 7.94E+03Pb[bhedtc]2 DMSO 7.93E-06 0.1223 1.54E+04

7.93E-06 0.3025 3.81E+047.93E-06 0.2363 2.98E+047.93E-06 0.2263 2.85E+047.93E-06 0.0023 2.90E+02

K[UO2(bhedtc)3] DMSO 9.18E-06 0.3247 3.54E+049.18E-06 0.2983 3.25E+049.18E-06 0.01685 1.84E+03

Zn[bhedtc]2 DMSO 1.22E-05 0.0031 2.50E+021.22E-05 0.0217 1.78E+03

Mass SpecComplexes Mass/Charge

ratio (m/z)Molecular

Weight (amu)

Ca[bhedtc]2 401.2 400.2

Cr[bhedtc]3 ~ ~

Zn[bhedtc]2 425.0 424.0

Hg[bhedtc]2 563.0 562.0

K[UO2(bhedtc)3] 810.4 849.5

Pb[bhedtc]2 591.0 568.0

*Central Analytical Laboratory at University of Colorado at Boulder

Elemental AnalysisComplexes % Carbon % Hydrogen % NitrigenPb[bhedtc]2 Calculated 21.16 3.55 4.93

Actual 21.22 3.47 4.88

21.27 3.34 4.86K[UO2(bhedtc)3] Calculated 21.2 3.56 4.94

Actual 18.12 2.74 4.08

17.93 2.7 3.94Cr[bhedtc]3 Calculated 30.39 5.1 7.09

Actual 16.19 3.94 3.52

16.39 3.92 3.65Ca[bhedtc]2 Calculated 29.98 5.03 6.99

Actual 9.94 1.36 2.18

9.74 1.46 2.18

8.82 1.45 1.86

*Columbia Analytical Services, Tucson, Arizona

Conclusion

• Study of Zinc and Mercury is complete

• Calcium, Chromium, and Uranium have a promising beginning

• New complex formed– Pb[bhedtc]2

N

C

S

S

HO

OH

N

C

S

S

OH

HO

Pb

Future Work

• Self-Assembly

• Additional trials

• Rotary evaporator

• Atomic Absorption Spectroscopy

• Attempt more metals

Acknowledgements

• Big Thanks:– McDaniel College Chemistry Department– Dr. Craig for the opportunity– Dr. Smith for advising the seminar process– Fran Wetzel for supplying reagents– Teresa Tilyou for her knowledge and assistance– Thao Tran and Kevin Bowman

References

• Pages, A.; Casas, J.S.; Sanchez, A.; Sordo, J.; Bravo, J.; Gayoso, M. Dithiocarbamates in Heavy Metal Poisoning: Complexes of N,N-di(2-hydroxyethyl)dithiocarbamate with Zn(II), Cd(II), Hg(II), CH3Hg(II), and C6H5Hg(II). J. Inorg. Biochem. 1985, 25, 35-42.

• Fenton, D.E. More metalloenzymes. Biocoordination Chemistry; Oxford University Press Inc.: New York, 1995; pp 60-80.

• Johnston, M. Genetic evidence that zinc is an essential co-factor in the DNA binding domain of GAL4 protein. Nature. 1987, 328, 353-355.

• Facts About Dietary Supplements: Zinc. http://ods.od.nih.gov/factsheets/cc/zinc.html#what (accessed April 17, 2008), National Institute of Health, Office of Dietary Supplements.

• Zinc in Drinking-water: Background document for development of WHO Guidelines for Drinking-water Quality; Technical Report for World Health Organization: Geneva, CH, 2003.

• Mercury in Health Care; Policy Paper for World Health Organization: Geneva, CH, August 2005.

• Exposure to Mercury: A Major Public Health Concern; Policy Paper for World Health Organization: Geneva, CH, 2007.

References• Depleted uranium. http://www.who.int/mediacentre/factsheets/fs257/en/ (accessed April

17, 2008), World Health Organization.

• Lead in Paint, Dust, and Soil. http://epa.gov/lead/pubs/leadinfo.htm#facts (accessed August 15, 2008), Environmental Protection Agency.

• Dietary Supplement Fact Sheet: Chromium. http://ods.od.nih.gov/factsheets/chrmoium.asp (accessed February 19, 2009), National Institute of Health, Office of Dietary Supplements.

• Dietary Supplement Fact Sheet: Calcium. http://ods.od.nih.gov/factsheets/calcium.asp (accessed August 7, 2008), National Institute of Health, Office of Dietary Supplements.

• Zhong, Y.; Zhang, W.; Fan J.; Tan, M.; Lai, C.S.; Tiekink, E.R.T. Bis[μ-N,N- bis(2- hydroxyethyl)dithiocarbamato]-1:2κ3S,S’:S’;2:1κ3S,S’:S’-bis{[N,N-bis(2-hydroxyethyl)dithiocarbamate-κ2S,S’]cadmium(II)}. Acta Crystallogr., Sect. E: Struct. Rep. 2004, E60, m1633-m1635.

• Zingaro, R.A. The Reaction of Uranyl Ion with Xanthates and Diethyldithiocarbamate. J. Am. Chem. Soc. 1956, 78, 3568-3570.

• Skoog, D.; Holler, F.; Crouch, S. Principles of Instrumental Analysis, 6th ed.; Thomson Brooks/Cole: Belmont, CA; pp 526, 557-558, 560-562.

Questions?