14 research outputs found
Syntheses and Structures of Mononuclear, Dinuclear and Polynuclear Silver(I) Complexes of 2‑Pyrazole-Substituted 1,10-Phenanthroline Ligands
A series of mononuclear, dinuclear and polynuclear silverÂ(I)
complexes
(<b>1</b>–<b>6</b>) bearing 2-pyrazole-substituted
1,10-phenanthroline derivatives (<b>L</b><sup><b>1</b></sup>, <sup><b>F</b></sup><b>L</b><sup><b>1</b></sup>, <b>L</b><sup><b>2</b></sup>) have been synthesized
and characterized by <sup>1</sup>H and <sup>13</sup>C NMR, IR spectroscopy,
elemental analysis, and single crystal X-ray diffraction. Reaction
of <b>L</b><sup><b>1</b></sup> (<b>L</b><sup>1</sup> = 2-(3,5-dimethylpyrazol-1-yl)-1,10-phenanthroline) with AgClO<sub>4</sub> or AgBF<sub>4</sub> afforded two dinuclear silverÂ(I) complexes
[Ag<sub>2</sub>(<b>L</b><sup><b>1</b></sup>)<sub>2</sub>(CH<sub>3</sub>CN)<sub>2</sub>]Â(ClO<sub>4</sub>)<sub>2</sub> (<b>1</b>) and [Ag<sub>2</sub>(<b>L</b><sup><b>1</b></sup>)<sub>2</sub>(CH<sub>3</sub>CN)<sub>2</sub>]Â(BF<sub>4</sub>)<sub>2</sub> (<b>2</b>), in which two [Ag<b>L</b><sup><b>1</b></sup>(CH<sub>3</sub>CN)]<sup>+</sup> units are linked by
Ag···Ag interaction (Ag···Ag separation:
3.208(2) and 3.248(1) Ã…, respectively). A one-dimensional polymer
{[Ag<b>L</b><sup><b>1</b></sup>]Â(BF<sub>4</sub>)}<sub>∞</sub> (<b>3</b>) consisting of an infinite ···Ag···Ag···Ag···
chain (Ag···Ag separation: 3.059(1) Å), as well
as a dinuclear complex [Ag<sub>2</sub>(ClO<sub>4</sub>)<sub>2</sub>(<b>L</b><sup><b>1</b></sup>)<sub>2</sub>] (<b>4</b>) in which the perchlorate anions instead of solvents are involved
in the metal coordination, have also been obtained. The mononuclear
complex [AgÂ(<sup><b>F</b></sup><b>L</b><sup><b>1</b></sup>)<sub>2</sub>]Â(BF<sub>4</sub>) (<b>5</b>) was synthesized
from <sup><b>F</b></sup><b>L</b><sup><b>1</b></sup> (<sup><b>F</b></sup><b>L</b><sup><b>1</b></sup> = 2-(3,5-bisÂ(trifluoromethyl)Âpyrazol-1-yl)-1,10-phenanthroline)
and AgBF<sub>4</sub>, while the dinuclear [Ag<sub>2</sub>(BF<sub>4</sub>)<sub>2</sub>(<b>L</b><sup><b>2</b></sup>)<sub>2</sub>] (<b>6</b>) was isolated from <b>L</b><sup><b>2</b></sup> (<b>L</b><sup><b>2</b></sup> = 2-[<i>N</i>-(3-methyl-5-phenylpyrazole)]-1,10-phenanthroline). The photoluminescence
properties of the ligands and complexes <b>1</b>–<b>6</b> have been studied both in the solid state and in solution
Syntheses and Structures of Mononuclear, Dinuclear and Polynuclear Silver(I) Complexes of 2‑Pyrazole-Substituted 1,10-Phenanthroline Ligands
A series of mononuclear, dinuclear and polynuclear silverÂ(I)
complexes
(1–6) bearing 2-pyrazole-substituted
1,10-phenanthroline derivatives (L1, FL1, L2) have been synthesized
and characterized by 1H and 13C NMR, IR spectroscopy,
elemental analysis, and single crystal X-ray diffraction. Reaction
of L1 (L1 = 2-(3,5-dimethylpyrazol-1-yl)-1,10-phenanthroline) with AgClO4 or AgBF4 afforded two dinuclear silverÂ(I) complexes
[Ag2(L1)2(CH3CN)2]Â(ClO4)2 (1) and [Ag2(L1)2(CH3CN)2]Â(BF4)2 (2), in which two [AgL1(CH3CN)]+ units are linked by
Ag···Ag interaction (Ag···Ag separation:
3.208(2) and 3.248(1) Ã…, respectively). A one-dimensional polymer
{[AgL1]Â(BF4)}∞ (3) consisting of an infinite ···Ag···Ag···Ag···
chain (Ag···Ag separation: 3.059(1) Å), as well
as a dinuclear complex [Ag2(ClO4)2(L1)2] (4) in which the perchlorate anions instead of solvents are involved
in the metal coordination, have also been obtained. The mononuclear
complex [AgÂ(FL1)2]Â(BF4) (5) was synthesized
from FL1 (FL1 = 2-(3,5-bisÂ(trifluoromethyl)Âpyrazol-1-yl)-1,10-phenanthroline)
and AgBF4, while the dinuclear [Ag2(BF4)2(L2)2] (6) was isolated from L2 (L2 = 2-[N-(3-methyl-5-phenylpyrazole)]-1,10-phenanthroline). The photoluminescence
properties of the ligands and complexes 1–6 have been studied both in the solid state and in solution
Magnesium−Magnesium Bond Stabilized by a Doubly Reduced α-Diimine: Synthesis and Structure of [K(THF)<sub>3</sub>]<sub>2</sub>[LMg−MgL] (L = [(2,6-<sup><i>i</i></sup>Pr<sub>2</sub>C<sub>6</sub>H<sub>3</sub>)NC(Me)]<sub>2</sub><sup>2−</sup>)
Magnesium−Magnesium Bond Stabilized by a Doubly Reduced α-Diimine: Synthesis and Structure of [K(THF)3]2[LMg−MgL] (L = [(2,6-iPr2C6H3)NC(Me)]22−
Magnesium−Magnesium Bond Stabilized by a Doubly Reduced α-Diimine: Synthesis and Structure of [K(THF)<sub>3</sub>]<sub>2</sub>[LMg−MgL] (L = [(2,6-<sup><i>i</i></sup>Pr<sub>2</sub>C<sub>6</sub>H<sub>3</sub>)NC(Me)]<sub>2</sub><sup>2−</sup>)
Magnesium−Magnesium Bond Stabilized by a Doubly Reduced α-Diimine: Synthesis and Structure of [K(THF)3]2[LMg−MgL] (L = [(2,6-iPr2C6H3)NC(Me)]22−
Homometallic Silver(I) Complexes of a Heterotopic NHC-Bridged Bis-Bipyridine Ligand
By varying the metal to ligand ratio, stepwise formation
of a series
of homonuclear silverÂ(I) complexes of a carbene-bridged bis-bipyridine
ligand (L) was achieved. In the mononuclear 1:2 complex [AgL2]Br (1) only the carbene carbon is involved in the metal
coordination, while both of the 2,2′-bipyridine (bpy) arms
are free. When the amount of silverÂ(I) ion was increased, isomorphous
2:2 dinuclear complexes with different counteranions, [Ag2L2]ÂX2 (X = Br– (2a), PF6– (2b), BPh4– (2c)), were synthesized from the
ligand LX, in which the carbene carbon and one of the bpy units participate
in the coordination with silverÂ(I) ions. Further addition of AgI salt afforded the one-dimensional coordination polymer {[Ag3L2]Â(PF6)3·4CH3CN}n (3), wherein the hanging
bipyridine units also coordinate with AgI and thus all
the coordination sites of the ligand are employed. The results reveal
the preference of AgI ion for the carbene carbon donor
rather than the bpy units. The synthesis, structures, and interconversion
of the complexes and the counteranion effects on the structures are
reported, and the luminescent properties of the ligand LX and the
silver complexes have also been studied
Homometallic Silver(I) Complexes of a Heterotopic NHC-Bridged Bis-Bipyridine Ligand
By varying the metal to ligand ratio, stepwise formation
of a series
of homonuclear silverÂ(I) complexes of a carbene-bridged bis-bipyridine
ligand (L) was achieved. In the mononuclear 1:2 complex [AgL<sub>2</sub>]Br (<b>1</b>) only the carbene carbon is involved in the metal
coordination, while both of the 2,2′-bipyridine (bpy) arms
are free. When the amount of silverÂ(I) ion was increased, isomorphous
2:2 dinuclear complexes with different counteranions, [Ag<sub>2</sub>L<sub>2</sub>]ÂX<sub>2</sub> (X = Br<sup>–</sup> (<b>2a</b>), PF<sub>6</sub><sup>–</sup> (<b>2b</b>), BPh<sub>4</sub><sup>–</sup> (<b>2c</b>)), were synthesized from the
ligand LX, in which the carbene carbon and one of the bpy units participate
in the coordination with silverÂ(I) ions. Further addition of Ag<sup>I</sup> salt afforded the one-dimensional coordination polymer {[Ag<sub>3</sub>L<sub>2</sub>]Â(PF<sub>6</sub>)<sub>3</sub>·4CH<sub>3</sub>CN}<sub><i>n</i></sub> (<b>3</b>), wherein the hanging
bipyridine units also coordinate with Ag<sup>I</sup> and thus all
the coordination sites of the ligand are employed. The results reveal
the preference of Ag<sup>I</sup> ion for the carbene carbon donor
rather than the bpy units. The synthesis, structures, and interconversion
of the complexes and the counteranion effects on the structures are
reported, and the luminescent properties of the ligand LX and the
silver complexes have also been studied
Tris Chelating Phosphate Complexes of Bis(thio)urea Ligands
Two bisurea (L1, L2) and one bisthiourea (L3) ligands were synthesized and their anion coordination behavior
was studied. These ligands can readily form the tris chelates [PO4(L)3]3– (1, 5, and 6) with phosphate ion (PO43–) in the solid state, in which the anion
is coordinated by six urea groups through 12 hydrogen bonds. Solution
binding studies by 1H NMR and UV–vis spectroscopy
revealed different binding properties of the ligands toward phosphate
ion. While the bisÂ(p-nitrophenyl)-substituted bisurea L1 retains the 3:1 (host to guest)
binding ratio in solution, the diethyl derivative L2 only forms 1:1 complex with phosphate ion. The
more acidic thiourea L3 undergoes
deprotonation/decomposition in the presence of phosphate ion. Moreover,
the sulfate complex (2) of L1 and bicarbonate (3) and carbonate (4) complexes of L2 have also
been obtained, which show lower coordination numbers both in the solid
state and in solution
Synthesis and Structure of a Zinc−Zinc-Bonded Compound with a Monoanionic α-Diimine Ligand, [LZn−ZnL] (L = [(2,6-<sup><i>i</i></sup>Pr<sub>2</sub>C<sub>6</sub>H<sub>3</sub>)NC(Me)]<sub>2</sub><sup>−</sup>)
A zinc−zinc-bonded compound with a monoanionic α-diimine ligand, [LZn−ZnL] (L = [(2,6-iPr2C6H3)NC(Me)]2−) (3), has been synthesized by the reaction of ZnCl2 and [Na2L]. The Zn−Zn bond distance (2.3403(18) Å) is shorter than that in the analogues with the dianionic ligand
Synthesis and Structure of a Zinc−Zinc-Bonded Compound with a Monoanionic α-Diimine Ligand, [LZn−ZnL] (L = [(2,6-<sup><i>i</i></sup>Pr<sub>2</sub>C<sub>6</sub>H<sub>3</sub>)NC(Me)]<sub>2</sub><sup>−</sup>)
A zinc−zinc-bonded compound with a monoanionic α-diimine ligand, [LZn−ZnL] (L = [(2,6-iPr2C6H3)NC(Me)]2−) (3), has been synthesized by the reaction of ZnCl2 and [Na2L]. The Zn−Zn bond distance (2.3403(18) Å) is shorter than that in the analogues with the dianionic ligand
Tris Chelating Phosphate Complexes of Bis(thio)urea Ligands
Two bisurea (L1, L2) and one bisthiourea (L3) ligands were synthesized and their anion coordination behavior
was studied. These ligands can readily form the tris chelates [PO4(L)3]3– (1, 5, and 6) with phosphate ion (PO43–) in the solid state, in which the anion
is coordinated by six urea groups through 12 hydrogen bonds. Solution
binding studies by 1H NMR and UV–vis spectroscopy
revealed different binding properties of the ligands toward phosphate
ion. While the bisÂ(p-nitrophenyl)-substituted bisurea L1 retains the 3:1 (host to guest)
binding ratio in solution, the diethyl derivative L2 only forms 1:1 complex with phosphate ion. The
more acidic thiourea L3 undergoes
deprotonation/decomposition in the presence of phosphate ion. Moreover,
the sulfate complex (2) of L1 and bicarbonate (3) and carbonate (4) complexes of L2 have also
been obtained, which show lower coordination numbers both in the solid
state and in solution