Attempted syntheses of transition metal and lanthanide (dialkylamino)squarates. The hydrolysis problem

The synthesis of first-row transition metal and lanthanide dialkylaminosquarates similar to lead(II) analogues prepared earlier proved to be unsuccessful owing to the hydrolysis of the amino groups on the ligands. The salt (Mn(H2O)6)(HC4O3NH2)2, wherein the metal remained uncomplexed to the ligand, was the only compound successfully prepared that contained an amino group. The transition metal and lanthanide ions apparently intervened in the hydrolysis.