Removal of Paramagnetic Ions Prior to Analysis of Organic Reactions in Aqueous Solutions by NMR Spectroscopy

This article describes a method for improving 1H NMR spectra of aqueous samples containing paramagnetic metals by precipitation metal cations with variety counteranions. The addition hydroxide, phosphate, carbonate, and arsenate to solutions transition such as Fe2+ Mn2+ can reduce line broadening improve the ability spectrometer lock on signal deuterium. is most effective under strongly alkaline conditions, care must be taken observe whether organic substrates undergo side reactions or are themselves removed from solution upon precipitating salts. As demonstration practical value method, we show that spectroscopy used monitor transition-metal-mediated hydrolysis glycylglycine (Gly2).