Cadmium II Complexes with a-Amino Acids

Structural studies on cadmium(II) complexes with amino acids include a vast number of compounds. Therefore, hereafter, we will focus exclusively on those complexes that contain one or more of the twenty essential a-amino acids. 

Complexes in which only the a-amino acid is coordinated to the cadmium can be monomeric, such as [Cd(L-Hhis)2] 2H20, in which the cadmium is octahedrally 

Carballo, Castineiras, Dommguez-Martm, Garcia-Santos, and Niclos-Gutierrez 

2 a-Amino Acid Complexes with Water as Co-ligand 

There are a number of known polymeric and monomeric cadmium complexes with a-amino acids that contain coordinated water. An example of a monomer is [Cd(L-ala)2(H20)] H20 where the metal is octahedrally coordinated by two alaninate(l-) ligands that act as cis-0,0-trans-N,N chelating bidentate ligands [Cd-O, 2.326(5) A, Cd-N, 2.334(5) A] and by two water molecules that occupy cis positions [Cd-O, 2.296(4) A] [44]. 

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