Research Article
Musa E. Mohamed
Abstract
The complexes between amino acids (l-glutamic acid and l-phenylalanine) and lanthanide Metals (La+3 and Yb+3) have been prepared and characterized using a variety of techniques including, infrared spectroscopy,1H NMR, 13C NMR, elemental analysis and metal contents. The 1H NMR and 13C NMR spectrum of the lanthanides complexes of l-glutamic acid and lphenylalanine undergo a shift to lower and higher field when it was compared with free amino acids. The large upfield shift observed in the case of Ytterbium complexes, because Ytterbium metal is more contracted than Lanthanum metal. The 13C downfield shift indicates a lower electron density at the carbon with consequent downfield shift observed on the α-H attached to it increasing its acidity.