Facile One‐Pot Route toward Water‐Soluble Lanthanide–Copper–Glycinehydroximate 15‐Metallacrown‐5 Complexes. Issue 31 (16th October 2015) - Katkova, Marina A.
Abstract: Among the Ln[15MCCuRha ‐5] metallacrowns (MC; Rha = R‐substituted hydroximate ligands), the simple glycinehydroximate (Glyha) complex is presented as the primary model for studying various aspects of the guest interaction with the Ln III ion. We report a one‐pot synthesis of several glycinehydroximate LnL[15MCCuGlyha ‐5] derivatives in the presence of calcium compounds. The complexes with bidentate nitrate ion Nd(NO3 )[15MCCu II Glyha ‐5](NO3 )2 (1 ), bidentate acetate Y(CH3 COO)[15MCCu II Glyha ‐5](NO3 )2 (2 ), bridging nitrate La(NO3 )[15MCCu II Glyha ‐5](NO3 )2 (3 ), and bidentate lactate Gd(CH3 CHOCOO)[15MCCu II Glyha ‐5]Cl2 [4 (Gd)] have been prepared and characterized by X‐ray analysis. The lactate was chosen as an example of the essential oxy‐anions that exist as metabolites in all living organisms. We examined the lanthanide‐induced NMR spectroscopy shifting ability of a series of lactate4 (Ln) metallacrown complexes (Ln = La, Y, Ce, Pr, Nd, Sm, Eu, Gd, Tb, or Dy). The corresponding Gd III complex was characterized by 1 H NMR spectroscopy relaxometric techniques in aqueous media. Abstract : A one‐pot strategy using calcium compounds has enabled access to various water‐soluble metallacrown (MC) Ln[15MCCuGlyha ‐5] derivatives with glycinehydroximate (Glyha). The examples include bidentate nitrate Nd(NO3 )[15MCCu II Glyha ‐5](NO3 )2 (1 ), bidentate acetate Y(OAc)[15MCCu II Glyha ‐5](NO3 )2 (2 ), bridging nitrate La(NO3 )[15MCCu II Glyha ‐5](NO3 )2 (3 ), and lactate Gd(lactate)[15MCCu II Glyha ‐5]Cl2 (4 ).