[Flood18]

I recently came across a paper that used benzene as opposed to CDCL3 as an NMR solvent to improve the spectra...Why would this improve the spectra?  I assume it involves the special magnetic properties of benzene.  They also heated the sample to 70 C, if that has anything to do with it, thanks.

[DrCMS]

I'd guess it was just a better solvent so they could dissolved more sample in the C₆D₆ and get a cleaner spectra that or the product had peaks in the same place as the CDCl₃

[Flood18]

Not really sure about that, just said it resolved the spectrum....Not too sure what peaks would have shown up at 7.3 though.

[g-bones]

sometimes using benzene or toluene as a solvent helps to resolve aromatic protons more cleanly. 

[ardbeg]

and if they heated it to 70 C then the CDCl3 would boil off and the spectrometer wouldnt be happy...

[orgopete]

All solvents can have an effect on the chemical shifts of the solutes, even the TMS. That is why the solvent is noted in determining the NMR. If you obtain a spectrum of the same sample in a different solvent, it is not unusual to see small to unexpected shifts occurring.

Without the structure being given, it is very difficult to predict the purpose of using benzene. When I was in grad school (years ago), I used benzene to induce shifts in methyl ketones to determine whether they were axial or equatorial by the difference in the shift in benzene.

[discodermolide]

I recently came across a paper that used benzene as opposed to CDCL3 as an NMR solvent to improve the spectra...Why would this improve the spectra?  I assume it involves the special magnetic properties of benzene.  They also heated the sample to 70 C, if that has anything to do with it, thanks.

You get a so-called aromatic solvent induced shift. Depending on where the protons lie with respect to the pi system of benzene they move up or downfield, thus overlapping signals in CDCl3 may be resolved using this method.