Stereoisomeric coordination polymers based on facial and meridional six-coordinate dysprosium(iii )

Abstract

Due to the small difference in the chemical properties of facial (fac) and meridional (mer) stereoisomers, selective synthesis of one of the isomers is challenging, especially for lanthanide complexes. By...

Slow magnetic relaxation of mononuclear complexes based on uncommon Kramers lanthanide ions CeIII, SmIII and YbIII

“…38 By using rigid or flexible bidentate phosphine oxide ligands, we reported the first Sm III -SIM with D 5h equatorial compressed LFs, 19 as well as three stereoisomeric coordination polymers based on facial and meridional six-coordinate Dy III . 39 This study set out to synthesize and investigate the magnetic properties of mono-nuclear complexes based on a rigid phosphine oxide ligand dppbO 2 (1,2-bis(diphenylphosphino) benzene dioxide) and three uncommon Kramer ions Ce III , Sm III and Yb III . By solvothermal reactions, [Ce(dppbO 2 ) 2 Cl 3 ] (1), [Sm(dppbO 2 ) 2 Cl 3 ] (2) and [Yb(dppbO 2 ) 2 Cl 2 ]Cl (3) were obtained.…”

“…38 By using rigid or flexible bidentate phosphine oxide ligands, we reported the first Sm III -SIM with D 5h equatorial compressed LFs, 19 as well as three stereoisomeric coordination polymers based on facial and meridional six-coordinate Dy III . 39…”

N^N^C-Cyclometalated rhodium(iii) complexes with isomeric pyrimidine-based ligands: unveiling the impact of isomerism on structural motifs, luminescence and cytotoxicity

“…the ability of compounds with identical molecular formulae to exist in spatially different forms is one of the most fundamental ideas in chemistry. [1][2][3] Revealing the impact of isomerism on crystal structures, [4][5][6][7][8][9][10][11][12] and chemical properties, [13][14][15][16][17][18][19][20][21] as well as physical [22][23][24][25][26][27][28][29][30][31][32][33][34] and biological properties [35][36][37][38][39] is of particular importance for establishing structure-property relationships which pave the way toward the more predictable design of substances with desirable properties. Despite various kinds of constitutional and configurational isomerism of metal complexes being well known, 40 ligand isomerism, which belongs to constitutional isomerism, is documented in literature to a considerably lesser extent than other types of the isomerism of complexes.…”

“…Here we report the synthesis of two isomeric pyrimidinebased ligands, 4-(3,5-dimethyl-1H-pyrazol-1-yl)-2,5-diphenylpyrimidine (HL 2,5 ) and 4-(3,5-dimethyl-1H-pyrazol-1-yl)-2,6diphenylpyrimidine (HL 2,6 ) (Scheme 2) and their rhodium(III) complexes [RhL 2,5 HL 2,5 and HL 2,6 belong to pyrazolyl-pyrimidine ligands 23,69-76 and contain the pyrazolyl group at the position 4 of the pyrimidine ring. Aided by the N 3 pyrimidinic atom, this group forms the N^N-chelating site of the ligand molecule.…”

“…Furthermore, the phenyl group at the position 2 of the pyrimidine ring can serve as a substrate for cyclometallation reactions with the platinum group metals. Thus, depending on the nature of metal ions, HL 2,5 and HL 2,6 can act as either neutral N^N-or anionic N^N^C-chelating ligands. The second phenyl group introduced at the positions 5 (HL 2,5 ) or 6 (HL 2,6 ) of the pyrimidine ring enforces different degrees of steric bulk in HL 2,5 and HL 2,6 .…”