There is a chemical shift difference between the metal coordinated and uncoordinated solvent. For example, normally methanol will give the value at 3.35 ppm suppose if it coordinate what will be the value? I got the triplet around 0.1 ppm will it be methanol? I have taken the NMR for my complex in DMSO. If it is possible kindly provide related articles.
Well, it will be unusual to have on peak on the proton NMR spectrum of methanol. There should be the peak for the methyl protons and another for the OH protons. The major observations in the case of complexation are slight changes in chemical shifts. Also, take not that coordination can take place through deprotonation, and hence, such a peak no longer appears in the spectrum of the complex. The type of chemical environment matters and so there should be no fixed values where which peak should appear, but we can talk of a range. Hope this helps.
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It is strongly depend on the character of your complex. Complex with strong ring current effect will shift your solvent pick to a higher field versus a complex with no ring current effect.
Well, it will be unusual to have one peak on the proton NMR spectrum of methanol. There should be the peak for the methyl protons and another for the OH protons. The major observations in the case of complexation are slight changes in chemical shifts. Also, take not that coordination can take place through deprotonation, and hence, such a peak no longer appears in the spectrum of the complex. The type of chemical environment matters and so there should be no fixed values where which peak should appear, but we can talk of a range. Hope this helps.
Please check out: Methyl Proton NMR Shifts of Coordinated Methanol in a Series of Co(CH,OH), X2+ Compounds by J.R.Vriesenga and Jerry Goodisman, Journal of Magnetic Resonance (1969), 20(1), 102-109. Available on the Internet:
surface.syr.edu/cgi/viewcontent.cgi?article=1077&context=che.
Also Characterization of DMSO Coordination to Palladium(II) in Solution and Insights into the Aerobic Oxidation Catalyst, Pd(DMSO)2(TFA)2, Tianning Diao, et al., Inorg. Chem. 2012 Nov. 5; 51(21): 11898-11909; available on the Internet, HHS Public Access. Table 1 gives IR and 1H NMR data on DMSO and transition metal-coordinated DMSO reported in the literature, as well as references (#10).
Is your complex a methanol one? If so, DMSO is a strong complexing agent, and can replace the methanol in the complex, especially since there is a lot more DMSO in the solution than coordinated methanol in the complex.
Best wishes in your research, Tony.
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