1. VV
Solution Precipitate
Cu
Ag
Fe
Zn
Co
Mn
Cr
Ni
Color
Metal Observations
60mg DA in 5mL DDI water
V
V
V
Department of Chemistry
and of Colorado
Colorado Springs
V
F
Background: Metal complexes are commonly formed by transition
metal ions and ligands. Ligands are molecules with extra electrons on
atoms like oxygen and nitrogen. These electrons form a bond by filling
the empty d-orbitals of the transition metal. Complexes are often very
colorful, which is evident of the splitting of the d-orbitals.
Synthesis of 1-benzyl-1H-1,2,3-triazole-4-carboxylic acid and
1-benzyl-1H-1,2,3-4,5-dicarboxylic acid for use as ligands in metal binding
Maggi Braasch-Turi, Allen Schoffstall*, & Renee Henry¥
Abstract: Allyl azide and many 1-benzyl-1H-1,2,3-triazole-4-carboxylic acid and 1-benzyl-1H-1,2,3-4,5-dicarboxylic acid were synthesized to be used as ligands for metal coordination complexes. Benzyl
bromide was reacted with sodium azide to form benzyl azide. Benzyl azide was reacted with methyl propiolate and dimethylacetylene dicarboxylate to form triazole derivatives via Huisgen “click”
cycloaddition. The methyl esters were converted to carboxylic acids via base-promoted hydrolysis. The corresponding monocarboxylic acid and dicarboxylic acid were used to form coordination complexes
with various transition metals. The dicarboxylic acid was reacted in a basic medium with a metal salt to form a precipitate. The metal salts produced Ag+, Fe2+, Fe3+, Zn2+, Co2+, Mn2+, Cr3+, and Ni2+ in
solution. The solids formed were analyzed with infrared spectroscopy (IR) and far infrared spectroscopy (FIR) to observe possible geometries of the complex.
Benzyl Azide3
Methyl 1-Benzyl-1H-1,2,3-triazole-4-carboxylate3,5
1-Benzyl-1H-1,2,3-triazole-4-carboxylic acid3,5
1-Benzyl-1H-1,2,3-triazole-4,5-dicarboxylic acid (DA)3,5,7
Metal Binding8
V
Motivation: A call for new ways to recycle metals was published in
C & EN’s April 2015 issue1. Naturally found metals and ores are
becoming scarce. Scientists are working towards recovering metals
from other sources, such as biosolids from sewage. Studies have shown
that biosolids are a valuable source of many lucrative metals. If a
sustainable method is discovered, metals could be recovered from
sewage sludge as well as from contaminated water and soil. This would
decrease the need for mining more metals from the ground.
Chloropentaamminecobalt (II) chloride Hexaamminecobalt(III) chloride
Tried 3 different procedures to isolate allyl azide
• Extracted with ethyl acetate & rotovap
• Co-evaporated
• Extracted with dichloromethane & rotovap
• Co-evaporated, 4.128% yield
• Extracted with dichloromethane & ice bath rotovap2
• 62.235% yield
This branch of research was discontinued, however, for future work,
this would still be a preferable starting material because of the allyl
group might easily be modified into other functionalities. Another
avenue would be to continue the synthesis in situ.
References:
In this study, new ligands were synthesized and analyzed for its
metal binding ability for the reclamation of metals in aqueous solution.
General Procedure4:
1) Dissolve ligand in DDI water
2) Add 1M sodium bicarbonate
dropwise until pH is 7
3) Dissolve metal salt
(Calculated from 3:1 ligand: metal ratio)
4) Stir overnight
5) Refrigerate for 2 hours
6) Vacuum filter precipitate
7) Rinse with ethanol and diethyl ether
8) Characterize with MIR and FIR
1:1 t-butanol:H2O
reflux, 1 hr
Sodium ascorbate, 1M CuSO4
1:1 t-butanol:H2O
reflux, 1 hr
THF, 3M NaOH
Reflux, 2 hrs
1:1 t-butanol:H2O
reflux, 2 hrs
THF, 3M NaOH
Reflux, 2 hrs
Acetone
63°C, 4 hrs
• Yellow-brown, oily liquid.
• 88.59% yield
Trial Combinations:
-20mg DA in 20mL DDI water
-60mg DA in 60mL DDI water
-60mg DA in 20mL DDI water
-60mg DA in 5mL DDI water
Results show less water and lots of
ligand produce more precipitate.
Precipitate started out
white. After a few days
of sitting out, the solid
turned brown.
No visible precipitate. The top
was left off the flask over the
weekend to evaporate the water
off to induce precipitation.
Fe2+ decayed to Fe3+ almost
immediately in solution. This was
possible due to the age of the ferrous
chloride tetrahydrate reagent bottle.
Precipitation occurred
almost immediately.
Precipitate starts out white
in solution, but turns
pink/purple when exposed
to light out of solution.
Zn metal should make white
complexes because of the full d-
orbital. Without a empty spaces in the
split d-orbital, electrons cannot jump
up to higher levels to produce colors.
Solution is pink, but
precipitate is a dark purple.
Solution is lavender, but
precipitate is a dark green.
Very small crystals have
formed in the other trials.
Lots of precipitate was
produced, however it
was blown away in the
fume hood.
Future Work:
• Metal binding experiments will be performed with 1-benzyl-1H-1,2,3-
triazole-4-carboxylic acid using 5mL DDI water and 60mg of the ligand.
FIR and MIR spectra will be taken to analyze for complex formation.
• Debenzylation of the ligands is another path for the ligands to see how
their geometries differ without the extra hindrance.
• White-yellow crystalline solid
• 93.01% yield
• Brown-yellow, very viscous oil
• 74.40% yield
• White, fluffy, crystalline solid
• 83.58% yield
M3+/2+/+ + 3DA [M(DA)3]3+/2+/+
This diagram1
shows how
certain metals
can be recycled
or how they are
currently unable
to be recycled.
Allyl Azide3
• Off-white crystalline solid
• 91.06% yield
1) Ritter, S.K. Wanted: New Ways to Recycle Metals. C&EN 2015, 93, pp 25-27.
2) Yang, B.; Zhang, H.; Peng, H.; Xu, Y.; Wu, B.; Weng, W.; Li, L.The Royal Society of Chemistry, 2013.
3) Butler, C. Lab Group Meeting, 2015.
4) Drake, H. Lab Group Meeting, 2015.
5) Moulin, F. Helvetica Chimica Acta, 1952,35, 167–180.
6) Yoshida, S.; Hatakeyama, Y.; Johmoto, K.; Uekusa, H.; Hosoya, T.Journal of the American Chemical Society
2014,136 (39), 13590–13593.
7) Georgiyants, V. A.; Perekhoda, L. O.Synthesis and study of 1-benzyl-1H-1,2,3-triazole-4,5-dicarboxylic acid,
2005,2, 3–6.
8) Lanjewar, R. B.; Waditwar, A. M.; Garg, A. N.Journal of Radioanalytical and Nuclear Chemistry, 1987,125, 75–84.
Acknowledgements:I would like to formally acknowledge the following people and organizations in
supporting me during the summer. Thank you very much for all of your help. I learned more this summer
than any laboratory class could ever teach me.
• National Science Foundation
• Department of Chemistry and Biochemistry at UCCS
• Dr. Allen Schoffstall
• Dr. Renee Henry
• Christopher Butler
• Dr. Al Hagedorn
Dimethyl 1-Benzyl-1H-1,2,3-triazole-4,5-dicarboxylate3,5,6
![VV
Solution Precipitate
Cu
Ag
Fe
Zn
Co
Mn
Cr
Ni
Color
Metal Observations
60mg DA in 5mL DDI water
V
V
V
Department of Chemistry
and of Colorado
Colorado Springs
V
F
Background: Metal complexes are commonly formed by transition
metal ions and ligands. Ligands are molecules with extra electrons on
atoms like oxygen and nitrogen. These electrons form a bond by filling
the empty d-orbitals of the transition metal. Complexes are often very
colorful, which is evident of the splitting of the d-orbitals.
Synthesis of 1-benzyl-1H-1,2,3-triazole-4-carboxylic acid and
1-benzyl-1H-1,2,3-4,5-dicarboxylic acid for use as ligands in metal binding
Maggi Braasch-Turi, Allen Schoffstall*, & Renee Henry¥
Abstract: Allyl azide and many 1-benzyl-1H-1,2,3-triazole-4-carboxylic acid and 1-benzyl-1H-1,2,3-4,5-dicarboxylic acid were synthesized to be used as ligands for metal coordination complexes. Benzyl
bromide was reacted with sodium azide to form benzyl azide. Benzyl azide was reacted with methyl propiolate and dimethylacetylene dicarboxylate to form triazole derivatives via Huisgen “click”
cycloaddition. The methyl esters were converted to carboxylic acids via base-promoted hydrolysis. The corresponding monocarboxylic acid and dicarboxylic acid were used to form coordination complexes
with various transition metals. The dicarboxylic acid was reacted in a basic medium with a metal salt to form a precipitate. The metal salts produced Ag+, Fe2+, Fe3+, Zn2+, Co2+, Mn2+, Cr3+, and Ni2+ in
solution. The solids formed were analyzed with infrared spectroscopy (IR) and far infrared spectroscopy (FIR) to observe possible geometries of the complex.
Benzyl Azide3
Methyl 1-Benzyl-1H-1,2,3-triazole-4-carboxylate3,5
1-Benzyl-1H-1,2,3-triazole-4-carboxylic acid3,5
1-Benzyl-1H-1,2,3-triazole-4,5-dicarboxylic acid (DA)3,5,7
Metal Binding8
V
Motivation: A call for new ways to recycle metals was published in
C & EN’s April 2015 issue1. Naturally found metals and ores are
becoming scarce. Scientists are working towards recovering metals
from other sources, such as biosolids from sewage. Studies have shown
that biosolids are a valuable source of many lucrative metals. If a
sustainable method is discovered, metals could be recovered from
sewage sludge as well as from contaminated water and soil. This would
decrease the need for mining more metals from the ground.
Chloropentaamminecobalt (II) chloride Hexaamminecobalt(III) chloride
Tried 3 different procedures to isolate allyl azide
• Extracted with ethyl acetate & rotovap
• Co-evaporated
• Extracted with dichloromethane & rotovap
• Co-evaporated, 4.128% yield
• Extracted with dichloromethane & ice bath rotovap2
• 62.235% yield
This branch of research was discontinued, however, for future work,
this would still be a preferable starting material because of the allyl
group might easily be modified into other functionalities. Another
avenue would be to continue the synthesis in situ.
References:
In this study, new ligands were synthesized and analyzed for its
metal binding ability for the reclamation of metals in aqueous solution.
General Procedure4:
1) Dissolve ligand in DDI water
2) Add 1M sodium bicarbonate
dropwise until pH is 7
3) Dissolve metal salt
(Calculated from 3:1 ligand: metal ratio)
4) Stir overnight
5) Refrigerate for 2 hours
6) Vacuum filter precipitate
7) Rinse with ethanol and diethyl ether
8) Characterize with MIR and FIR
1:1 t-butanol:H2O
reflux, 1 hr
Sodium ascorbate, 1M CuSO4
1:1 t-butanol:H2O
reflux, 1 hr
THF, 3M NaOH
Reflux, 2 hrs
1:1 t-butanol:H2O
reflux, 2 hrs
THF, 3M NaOH
Reflux, 2 hrs
Acetone
63°C, 4 hrs
• Yellow-brown, oily liquid.
• 88.59% yield
Trial Combinations:
-20mg DA in 20mL DDI water
-60mg DA in 60mL DDI water
-60mg DA in 20mL DDI water
-60mg DA in 5mL DDI water
Results show less water and lots of
ligand produce more precipitate.
Precipitate started out
white. After a few days
of sitting out, the solid
turned brown.
No visible precipitate. The top
was left off the flask over the
weekend to evaporate the water
off to induce precipitation.
Fe2+ decayed to Fe3+ almost
immediately in solution. This was
possible due to the age of the ferrous
chloride tetrahydrate reagent bottle.
Precipitation occurred
almost immediately.
Precipitate starts out white
in solution, but turns
pink/purple when exposed
to light out of solution.
Zn metal should make white
complexes because of the full d-
orbital. Without a empty spaces in the
split d-orbital, electrons cannot jump
up to higher levels to produce colors.
Solution is pink, but
precipitate is a dark purple.
Solution is lavender, but
precipitate is a dark green.
Very small crystals have
formed in the other trials.
Lots of precipitate was
produced, however it
was blown away in the
fume hood.
Future Work:
• Metal binding experiments will be performed with 1-benzyl-1H-1,2,3-
triazole-4-carboxylic acid using 5mL DDI water and 60mg of the ligand.
FIR and MIR spectra will be taken to analyze for complex formation.
• Debenzylation of the ligands is another path for the ligands to see how
their geometries differ without the extra hindrance.
• White-yellow crystalline solid
• 93.01% yield
• Brown-yellow, very viscous oil
• 74.40% yield
• White, fluffy, crystalline solid
• 83.58% yield
M3+/2+/+ + 3DA [M(DA)3]3+/2+/+
This diagram1
shows how
certain metals
can be recycled
or how they are
currently unable
to be recycled.
Allyl Azide3
• Off-white crystalline solid
• 91.06% yield
1) Ritter, S.K. Wanted: New Ways to Recycle Metals. C&EN 2015, 93, pp 25-27.
2) Yang, B.; Zhang, H.; Peng, H.; Xu, Y.; Wu, B.; Weng, W.; Li, L.The Royal Society of Chemistry, 2013.
3) Butler, C. Lab Group Meeting, 2015.
4) Drake, H. Lab Group Meeting, 2015.
5) Moulin, F. Helvetica Chimica Acta, 1952,35, 167–180.
6) Yoshida, S.; Hatakeyama, Y.; Johmoto, K.; Uekusa, H.; Hosoya, T.Journal of the American Chemical Society
2014,136 (39), 13590–13593.
7) Georgiyants, V. A.; Perekhoda, L. O.Synthesis and study of 1-benzyl-1H-1,2,3-triazole-4,5-dicarboxylic acid,
2005,2, 3–6.
8) Lanjewar, R. B.; Waditwar, A. M.; Garg, A. N.Journal of Radioanalytical and Nuclear Chemistry, 1987,125, 75–84.
Acknowledgements:I would like to formally acknowledge the following people and organizations in
supporting me during the summer. Thank you very much for all of your help. I learned more this summer
than any laboratory class could ever teach me.
• National Science Foundation
• Department of Chemistry and Biochemistry at UCCS
• Dr. Allen Schoffstall
• Dr. Renee Henry
• Christopher Butler
• Dr. Al Hagedorn
Dimethyl 1-Benzyl-1H-1,2,3-triazole-4,5-dicarboxylate3,5,6](https://image.slidesharecdn.com/c61469b8-c1e6-4c8b-97f5-197a2d1d3559-160203215630/85/REU-POSTER-USE-THIS-ONE-1-320.jpg)
