Synthesis and photophysical properties of rare earth complexes bearing silanediamido ligands Me₂Si(NAryl)₂²⁻ (Aryl = Dipp, Mes)

Abstract

A series of rare earth (RE) chloride complexes bearing silanediamido ligands (LAryl)2– = Me2Si(NAryl)22– with bulky substituents, Aryl = mesityl (Mes), and 2,6-diisopropylphenyl (Dipp) was synthesized by salt metathesis reactions....

Lanthanide complexes with a new luminescent iminophosphonamide ligand bearing phenylbenzothiazole substituents

“…However, the less intense emission around 580 nm arises from the two inner ligands around the metal cation. The latter is supported by our previous experience with silanediamide complexes 50,62 and the photophysical properties of phenyl-benzothiazole-based compounds, emitting at the same region. 35–37,63–65 Luminescence decay curves have a complicated three-exponential character, indicating multiple routes of energy dissipation (Table 2 and Fig.…”

Synthesis and photophysical properties of rare earth (La, Nd, Gd, Y, Ho) complexes with silanediamido ligands bearing a chelating phenylbenzothiazole chromophore

“…The mentioned Dipp-substituted ligand is known to form the [Sm III (L Dipp ) 2 ] À anion, obtained as a result of redox transformations from a neutral Sm(II) complex, 45 but when the metal to ligand stoichiometry 1 : 1 is maintained, monoligand complexes of both ligands can be purely obtained. 27,46 Even for the divalent Yb 2+ cation with an ionic radius comparable to those of early trivalent Ln 3+ cations (1.02 Å for CN = 6, 1.14 Å for CN = 8) the selective formation of the mono-substituted complex [Yb(L Dipp )(thf) 3 ] was observed. 47 In the case of L 2À , for the early lanthanides (La 3+ , Nd 3+ , Gd 3+ ), as well as Y 3+ , no monoligand complexes were found.…”

“…Recently we reported the synthesis of lanthanide complexes with silanediamide ligands bearing bulky aryl substituents at the N donor atoms, Me 2 Si(NAryl) 2 2À (Aryl = mesityl (Mes), 2,6diisopropylphenyl (Dipp)). 27 They were shown to be appropriate antennas for the excitation of Tb 3+ luminescence, giving QYs higher than those of b-diketiminate complexes with the same substituents. Silanediamino ligands are advantageous over many other monoanionic N,N 0 -donor ligands in that they bear 2À charge, thus providing stronger binding with Ln 3+ cations, and form a rigid {SiN 2 Ln} metallacycle upon complexation.…”