Synthesis and Characterization of New Strontium Complexes with Multidentate Ligands

摘要

A series of new strontium complexes,[Sr(tmtad)(btsa)]2(1),[Sr(ptmtad)(btsa)]2(2),[Sr(etmtad)(btsa)]2(3),[Sr(tmtad)(tmhd)]2(4),[Sr(ptmtad)(tmhd)]2(5),and [Sr(etmtad)(tmhd)]2(6),were successfully synthesized by substitution reactions between btsa,aminoalkoxide ligands,and tmhdH(btsa=bis(trimethylsilyl)amide,tmtadH=2,5,9,12-tetramethyl-2,5,9,12-tetraazatridecan-7-ol,ptmtadH=2,5,7,9,12-pentamethyl-2,5,9,12-tetraazatridecan-7-ol,etmtadH=7-ethyl-2,5,9,12-tetramethyl-2,5,9,12-tetraazatridecan-7-ol,tmhdH=2,2,6,6-tetramethyl-3,5-heptanedione).Thermogravimetric analysis(TGA)of the new strontium compounds showed low residual masses(4-11%)where complex 4 displayed the highest volatility and thermal stability.Single crystal X-ray study of complexes 1,3,and 6 revealed that the respective complexes crystalize in a triclinic space group as a dimer with a hexa-or hepta-coordination.Furthermore,dimethylamino nitrogen atoms of aminoalkoxide ligands are freely pendent without coordinating to the central strontium metal due to their steric hindrance on the coordination sphere.Compounds 1-6 were characterized by ~1H-and ~(13)C-nuclear magnetic resonance(NMR)spectroscopy,Fouriertransform infrared(FT-IR)spectroscopy,elemental analysis(EA),and thermogravimetric analysis.