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Anyone familiar with NMR of Cobalt complexes?
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+ Inorganic chemistry
+ Catalysis
+ Nuclear magnetic resonance
+ Metal complexes
+ Homogeneous catalysis
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Linda Smith
Anyone familiar with NMR of Cobalt complexes?
It is possible to get 1H NMR of Cobalt complexes even though it is Co(II), which is paramagnetic. I have 1H NMR of my own Co(II) complex with Tp ligand, but the chemical shift is very large. Like Dr Harding said, check Co complexes with Tp ligands. The person who works with these kind of complexes is Dr David Tierney of Miami University in Ohio. Reading some of his papers might be helpful.
It is possible to get 1H NMR of Cobalt complexes even though it is Co(II), which is paramagnetic. I have 1H NMR of my own Co(II) complex with Tp ligand, but the chemical shift is very large. Like Dr Harding said, check Co complexes with Tp ligands. The person who works with these kind of complexes is Dr David Tierney of Miami University in Ohio. Reading some of his papers might be helpful.
Dear Burgert, Sarina, David and Lava, Alright, you are all right. Above, I meant using the usual shift range and setup of 1H NMR (0-15ppm) or someone who is that familiar changing sweep widths or other parameters on the NMR. It also matters of course, what kind (size) of Co(II) complex is present. Here are some more references and approaches to paramagnetic NMR spectroscopy. Regards, Imre
Dear Burgert, Sarina, David and Lava, Alright, you are all right. Above, I meant using the usual shift range and setup of 1H NMR (0-15ppm) or someone who is that familiar changing sweep widths or other parameters on the NMR. It also matters of course, what kind (size) of Co(II) complex is present. Here are some more references and approaches to paramagnetic NMR spectroscopy. Regards, Imre
Thanks Dr Imre Yes the triazole ring is susbstituted at 1-position with Mesityl group and the protons from the three methyl groups are very clear in 1HNMR in one complex but in the other complex is not clear at all and this was my question what could be the reason behind the diffrent behavior of the two complexes (one has two ccordinated water molecules and the other has two methanol molecules, this is the only diffrence between the two complexes).
Thanks Dr Imre Yes the triazole ring is susbstituted at 1-position with Mesityl group and the protons from the three methyl groups are very clear in 1HNMR in one complex but in the other complex is not clear at all and this was my question what could be the reason behind the diffrent behavior of the two complexes (one has two ccordinated water molecules and the other has two methanol molecules, this is the only diffrence between the two complexes).
Dear Burgert, Sarina, David and Lava, Alright, you are all right. Above, I meant using the usual shift range and setup of 1H NMR (0-15ppm) or someone who is that familiar changing sweep widths or other parameters on the NMR. It also matters of course, what kind (size) of Co(II) complex is present. Here are some more references and approaches to paramagnetic NMR spectroscopy. Regards, Imre
Dear Burgert, Sarina, David and Lava, Alright, you are all right. Above, I meant using the usual shift range and setup of 1H NMR (0-15ppm) or someone who is that familiar changing sweep widths or other parameters on the NMR. It also matters of course, what kind (size) of Co(II) complex is present. Here are some more references and approaches to paramagnetic NMR spectroscopy. Regards, Imre
Thanks a lot for all of your contributions, now i have another question regarding the same complex : If i have a diunclear Co(II) complex it would be paramegnetic or diamagnetic ? and so i can expect it would give peaks in NMR or not? Thanks in advance
Thanks a lot for all of your contributions, now i have another question regarding the same complex : If i have a diunclear Co(II) complex it would be paramegnetic or diamagnetic ? and so i can expect it would give peaks in NMR or not? Thanks in advance
Thanks Dominik But the complex has coordinated water, so i think if i oxidize it the structure might change and coordinated water convert into OH or =O, I am not sure this will be helpful or not? we wait comments on this point.
Thanks Dominik But the complex has coordinated water, so i think if i oxidize it the structure might change and coordinated water convert into OH or =O, I am not sure this will be helpful or not? we wait comments on this point.
Dear Hussein, Do you mean then that the aqua complex is not detectable on 1HNMR? What is your deuterated solvent? Can you exclude exchange or other chemistry upon dissolution of your complex? Regards, Imre
Dear Hussein, Do you mean then that the aqua complex is not detectable on 1HNMR? What is your deuterated solvent? Can you exclude exchange or other chemistry upon dissolution of your complex? Regards, Imre
Some of us including me have ignored the second part of your question, i. e. your Co(II) complex is based on a functionalized triazole. Such a ring itself contains very few H-s to detect, which are probably in the very close vicinity of the paramagnetic Co. If you have spacious H-containing substituents (alkyl, aryl etc.) on your triazole that is another story (facilitation) for 1H NMR.
Some of us including me have ignored the second part of your question, i. e. your Co(II) complex is based on a functionalized triazole. Such a ring itself contains very few H-s to detect, which are probably in the very close vicinity of the paramagnetic Co. If you have spacious H-containing substituents (alkyl, aryl etc.) on your triazole that is another story (facilitation) for 1H NMR.
It is possible to get 1H NMR of Cobalt complexes even though it is Co(II), which is paramagnetic. I have 1H NMR of my own Co(II) complex with Tp ligand, but the chemical shift is very large. Like Dr Harding said, check Co complexes with Tp ligands. The person who works with these kind of complexes is Dr David Tierney of Miami University in Ohio. Reading some of his papers might be helpful.
It is possible to get 1H NMR of Cobalt complexes even though it is Co(II), which is paramagnetic. I have 1H NMR of my own Co(II) complex with Tp ligand, but the chemical shift is very large. Like Dr Harding said, check Co complexes with Tp ligands. The person who works with these kind of complexes is Dr David Tierney of Miami University in Ohio. Reading some of his papers might be helpful.
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Dear Burgert, Sarina, David and Lava,
Alright, you are all right. Above, I meant using the usual shift range and setup of 1H NMR (0-15ppm) or someone who is that familiar changing sweep widths or other parameters on the NMR. It also matters of course, what kind (size) of Co(II) complex is present. Here are some more references and approaches to paramagnetic NMR spectroscopy.
Regards,
Imre
Dear Burgert, Sarina, David and Lava,
Alright, you are all right. Above, I meant using the usual shift range and setup of 1H NMR (0-15ppm) or someone who is that familiar changing sweep widths or other parameters on the NMR. It also matters of course, what kind (size) of Co(II) complex is present. Here are some more references and approaches to paramagnetic NMR spectroscopy.
Regards,
Imre
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Thanks a lot for all for their fruitful contribution and guide
I will try to run the sample again with a broad sweep width and see what might happen
Thanks a lot for all for their fruitful contribution and guide
I will try to run the sample again with a broad sweep width and see what might happen
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Thanks Dr Imre
Yes the triazole ring is susbstituted at 1-position with Mesityl group and the protons from the three methyl groups are very clear in 1HNMR in one complex but in the other complex is not clear at all and this was my question what could be the reason behind the diffrent behavior of the two complexes (one has two ccordinated water molecules and the other has two methanol molecules, this is the only diffrence between the two complexes).
Thanks Dr Imre
Yes the triazole ring is susbstituted at 1-position with Mesityl group and the protons from the three methyl groups are very clear in 1HNMR in one complex but in the other complex is not clear at all and this was my question what could be the reason behind the diffrent behavior of the two complexes (one has two ccordinated water molecules and the other has two methanol molecules, this is the only diffrence between the two complexes).
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You could also try to oxidize your complex to Co(III) and then run NMR again. This might give you valuable information.
You could also try to oxidize your complex to Co(III) and then run NMR again. This might give you valuable information.
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Dear Burgert, Sarina, David and Lava,
Alright, you are all right. Above, I meant using the usual shift range and setup of 1H NMR (0-15ppm) or someone who is that familiar changing sweep widths or other parameters on the NMR. It also matters of course, what kind (size) of Co(II) complex is present. Here are some more references and approaches to paramagnetic NMR spectroscopy.
Regards,
Imre
Dear Burgert, Sarina, David and Lava,
Alright, you are all right. Above, I meant using the usual shift range and setup of 1H NMR (0-15ppm) or someone who is that familiar changing sweep widths or other parameters on the NMR. It also matters of course, what kind (size) of Co(II) complex is present. Here are some more references and approaches to paramagnetic NMR spectroscopy.
Regards,
Imre
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Thanks a lot for all of your contributions, now i have another question regarding the same complex :
If i have a diunclear Co(II) complex it would be paramegnetic or diamagnetic ? and so i can expect it would give peaks in NMR or not?
Thanks in advance
Thanks a lot for all of your contributions, now i have another question regarding the same complex :
If i have a diunclear Co(II) complex it would be paramegnetic or diamagnetic ? and so i can expect it would give peaks in NMR or not?
Thanks in advance
More
VOTE
Thanks Dominik
But the complex has coordinated water, so i think if i oxidize it the structure might change and coordinated water convert into OH or =O, I am not sure this will be helpful or not? we wait comments on this point.
Thanks Dominik
But the complex has coordinated water, so i think if i oxidize it the structure might change and coordinated water convert into OH or =O, I am not sure this will be helpful or not? we wait comments on this point.
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There are quite some examples that dinuclear Co(II)-Co(III) complexes can be diamagnetic. Dinuclear Co(II) complexes can also be diamagnetic see for example https://books.google.hu/books?id=Owuv-c9L_IMC&pg=PA242&lpg=PA242&dq=dinuclear+Co+complex+diamagnetic&source=bl&ots=zXr__qlPk9&sig=maIPrQgR5_72kpEBTqs8ctFVMms&hl=en&sa=X&ved=0CDwQ6AEwA2oVChMIo9OMyIuMxgIVRNUUCh3ufQA2#v=onepage&q=dinuclear%20Co%20complex%20diamagnetic&f=false but this seems to be much less frequent. If you have triazole ligands with Co(II) the same applies what already is discussed above.
There are quite some examples that dinuclear Co(II)-Co(III) complexes can be diamagnetic. Dinuclear Co(II) complexes can also be diamagnetic see for example https://books.google.hu/books?id=Owuv-c9L_IMC&pg=PA242&lpg=PA242&dq=dinuclear+Co+complex+diamagnetic&source=bl&ots=zXr__qlPk9&sig=maIPrQgR5_72kpEBTqs8ctFVMms&hl=en&sa=X&ved=0CDwQ6AEwA2oVChMIo9OMyIuMxgIVRNUUCh3ufQA2#v=onepage&q=dinuclear%20Co%20complex%20diamagnetic&f=false but this seems to be much less frequent. If you have triazole ligands with Co(II) the same applies what already is discussed above.
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Dear Hussein,
Do you mean then that the aqua complex is not detectable on 1HNMR? What is your deuterated solvent? Can you exclude exchange or other chemistry upon dissolution of your complex?
Regards, Imre
Dear Hussein,
Do you mean then that the aqua complex is not detectable on 1HNMR? What is your deuterated solvent? Can you exclude exchange or other chemistry upon dissolution of your complex?
Regards, Imre
More
VOTE
Some of us including me have ignored the second part of your question, i. e. your Co(II) complex is based on a functionalized triazole. Such a ring itself contains very few H-s to detect, which are probably in the very close vicinity of the paramagnetic Co. If you have spacious H-containing substituents (alkyl, aryl etc.) on your triazole that is another story (facilitation) for 1H NMR.
Some of us including me have ignored the second part of your question, i. e. your Co(II) complex is based on a functionalized triazole. Such a ring itself contains very few H-s to detect, which are probably in the very close vicinity of the paramagnetic Co. If you have spacious H-containing substituents (alkyl, aryl etc.) on your triazole that is another story (facilitation) for 1H NMR.
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