[asdfTT123]

When running NMR (proton), does it matter what type of solvent is used as long as the compound is sufficiently soluble in the solvent?

For example, one of the compounds I would like to analyze was analyzed with methanol-d4 in literature but I find this solvent to be very expensive and hard to find.  I do however see that the compound is soluble with chloroform-d, which we already have in our lab.

Is there any difference I can expect from the spectra between these two solvents?  Is there any other rule of thumb I need to determine solvents other than solubility?

Many thanks.

[Dan]

The basic property you need is solubility. Due to the price of methanol-d₄ relative to CDCl₃, there is probably a good reason for using it (but not necessarily).

Using protic solvent, such as methanol-d₄, that undergoes H/D exchange with NH, OH, etc. can helpfully simplify the proton spectrum relative to an aprotic solvent like CDCl₃. Peak broadening from rotameric forms of Boc carbamates can also be significantly reduced in protic (or wet) solvents.

Chemical shifts are affected by solvent. Sometimes a spectrum run in e.g. CDCl₃ might have several overlapping peaks that make assignment difficult. It may be the case that the overlap is much less in a different solvent. If you run yours in CDCl₃ you will see a similar pattern of signals as reported in methanol-d₄ (plus exchangeable OH/NH), but the shifts will be not be exactly the same.