Help with 1H NMR Spectra (Will Choose Best Answer)?
 

Explain why the two sets of nitrogen protons in the 1H NMR spectrum of Dulcin have such different chemical shifts. The spectra is shown here: http://i134.photobucket.com/albums/q101/lholcomb07/1HNMRSpectraforDulcin001.jpgAny help would be greatly appreciated.

Help with 1H NMR Spectra (Will Choose Best Answer)?
 

IN DMSO (makes a big difference here) So you have an urea derivative. the NH is around 8.5 ppm and then NH2 is around 5.8 ppm. Don't forget we have an electron-withdrawing group - (Phenyl)DMSO can hydrogen bind to the NH groups so that is shifted downfield, why it chooses the NH versus the NH2 is a good question but that is the fact. In CDCL3 I suspect the shift differences would not be as great.<br />
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