8 research outputs found
Double-Stranded Binuclear Helicates and Helicity Modulation
All of the reported
self-assembled complexes of <i>cis</i>-Pd<sub>2</sub>Lā²<sub>2</sub>L<sub>2</sub> formulation, where
Lā² stands for a chelating bidentate ligand and L for a nonchelating
bidentate ligand, are ānon-helicalā. We disclose here
the debut of the long awaited āhelicateā type architecture
of the <i>cis-</i>Pd<sub>2</sub>Lā²<sub>2</sub>L<sub>2</sub> formulation. In the present work, the term Lā² stands
for tetramethylethylenediamine (<i>tmeda</i>) and L stands
for a (1<i>H</i>-imidazolyl)Āmethyl-appended bidentate nonchelating
ligand having a rigid spacer. The torsion angle between the two coordination
PdN<sub>4</sub> planes of a given āhelicateā is considered
here as its magnitude of helicity. Length of spacer unit (i.e., 1,4-benzene,
4,4ā²-biphenyl and 4,4ā²-<i>p</i>-terphenyl)
crafted in the backbone of L is found to impart such conformation
to the bound ligand moieties that the magnitude of helicity is modulated
Consequence of Presence and Absence of ĻāClouds at Strategic Locations of Designed Binuclear Pd(II) Complexes on Packing: Self-Assembly of Self-Assembly by Intermolecular Locking and Packing
Self-assembled binuclear coordination cages of general
formula
[Pd<sub>2</sub>(NāN)<sub>2</sub>(<b>L</b>)<sub>2</sub>]Ā(X)<sub>4</sub>, <b>1a/b</b>ā<b>4a/b</b> are
prepared by the combination of <i>N</i>,<i>N</i>ā²-bisĀ(<i>m</i>-pyridyl)Āurea, <b>L</b>, with
a variety of <i>cis</i>-protected palladiumĀ(II) components,
PdĀ(NāN)Ā(X)<sub>2</sub>. The <i>cis</i>-protecting
units āNāNā employed for the synthesis of <b>1</b>ā<b>4</b> are ethylenediamine (en), tetramethylethylenediamine
(tmeda), 2,2ā²-bipyridine (bpy), and 1,10-phenanthroline (phen),
respectively. The term āXā stands for nitrate and perchlorate
for <b>a</b> and <b>b</b>, respectively. The assemblies
are characterized by NMR and electrospray ionization mass spectrometry
(ESI-MS) techniques, and in some cases (i.e., <b>1a</b>,<b> 2b</b>,<b> 3b</b>,<b> 4a</b>, and <b>4b</b>) the structures are confirmed by single crystal X-ray diffraction.
The conformations of bound <b>L</b> in the crystal structures
of all the PdĀ(II) complexes are found to be <i>syn-syn</i>. The influence of the presence and absence of Ļ cloud at the <i>cis-</i>protecting units on the crystal packing has been studied
in detail. In the packing of [Pd<sub>2</sub>(phen)<sub>2</sub><b>L</b><sub>2</sub>]Ā(NO<sub>3</sub>)<sub>4</sub>, <b>4a</b>, one unit of [Pd<sub>2</sub>(phen)<sub>2</sub><b>L</b><sub>2</sub>]<sup>4+</sup> is associated with two other units by ĻāĻ
stacking interactions thus giving a one-dimensional growth as envisioned
on the basis of a design principle. In the case of [Pd<sub>2</sub>(en)<sub>2</sub>(<b>L)</b><sub>2</sub>]Ā(NO<sub>3</sub>)<sub>4</sub>, <b>1a</b>, and [Pd<sub>2</sub>(tmeda)<sub>2</sub>(<b>L</b>)<sub>2</sub>]Ā(ClO<sub>4</sub>)<sub>4</sub>, <b>2b</b>, such packing is not observed due to the absence of Ļ-cloud
at the strategic locations, instead notable H-bonding interactions
are seen. However, [Pd<sub>2</sub>(bpy)<sub>2</sub>(<b>L</b>)<sub>2</sub>]Ā(ClO<sub>4</sub>)<sub>4</sub>, <b>3b</b>, displays
a ĻāĻ interactions using only two units of [Pd<sub>2</sub>(bpy)<sub>2</sub>(<b>L</b>)<sub>2</sub>]<sup>4+</sup>(ClO<sub>4</sub>)<sup>ā</sup>
Consequence of Presence and Absence of ĻāClouds at Strategic Locations of Designed Binuclear Pd(II) Complexes on Packing: Self-Assembly of Self-Assembly by Intermolecular Locking and Packing
Self-assembled binuclear coordination cages of general
formula
[Pd<sub>2</sub>(NāN)<sub>2</sub>(<b>L</b>)<sub>2</sub>]Ā(X)<sub>4</sub>, <b>1a/b</b>ā<b>4a/b</b> are
prepared by the combination of <i>N</i>,<i>N</i>ā²-bisĀ(<i>m</i>-pyridyl)Āurea, <b>L</b>, with
a variety of <i>cis</i>-protected palladiumĀ(II) components,
PdĀ(NāN)Ā(X)<sub>2</sub>. The <i>cis</i>-protecting
units āNāNā employed for the synthesis of <b>1</b>ā<b>4</b> are ethylenediamine (en), tetramethylethylenediamine
(tmeda), 2,2ā²-bipyridine (bpy), and 1,10-phenanthroline (phen),
respectively. The term āXā stands for nitrate and perchlorate
for <b>a</b> and <b>b</b>, respectively. The assemblies
are characterized by NMR and electrospray ionization mass spectrometry
(ESI-MS) techniques, and in some cases (i.e., <b>1a</b>,<b> 2b</b>,<b> 3b</b>,<b> 4a</b>, and <b>4b</b>) the structures are confirmed by single crystal X-ray diffraction.
The conformations of bound <b>L</b> in the crystal structures
of all the PdĀ(II) complexes are found to be <i>syn-syn</i>. The influence of the presence and absence of Ļ cloud at the <i>cis-</i>protecting units on the crystal packing has been studied
in detail. In the packing of [Pd<sub>2</sub>(phen)<sub>2</sub><b>L</b><sub>2</sub>]Ā(NO<sub>3</sub>)<sub>4</sub>, <b>4a</b>, one unit of [Pd<sub>2</sub>(phen)<sub>2</sub><b>L</b><sub>2</sub>]<sup>4+</sup> is associated with two other units by ĻāĻ
stacking interactions thus giving a one-dimensional growth as envisioned
on the basis of a design principle. In the case of [Pd<sub>2</sub>(en)<sub>2</sub>(<b>L)</b><sub>2</sub>]Ā(NO<sub>3</sub>)<sub>4</sub>, <b>1a</b>, and [Pd<sub>2</sub>(tmeda)<sub>2</sub>(<b>L</b>)<sub>2</sub>]Ā(ClO<sub>4</sub>)<sub>4</sub>, <b>2b</b>, such packing is not observed due to the absence of Ļ-cloud
at the strategic locations, instead notable H-bonding interactions
are seen. However, [Pd<sub>2</sub>(bpy)<sub>2</sub>(<b>L</b>)<sub>2</sub>]Ā(ClO<sub>4</sub>)<sub>4</sub>, <b>3b</b>, displays
a ĻāĻ interactions using only two units of [Pd<sub>2</sub>(bpy)<sub>2</sub>(<b>L</b>)<sub>2</sub>]<sup>4+</sup>(ClO<sub>4</sub>)<sup>ā</sup>
Consequence of Presence and Absence of ĻāClouds at Strategic Locations of Designed Binuclear Pd(II) Complexes on Packing: Self-Assembly of Self-Assembly by Intermolecular Locking and Packing
Self-assembled binuclear coordination cages of general
formula
[Pd<sub>2</sub>(NāN)<sub>2</sub>(<b>L</b>)<sub>2</sub>]Ā(X)<sub>4</sub>, <b>1a/b</b>ā<b>4a/b</b> are
prepared by the combination of <i>N</i>,<i>N</i>ā²-bisĀ(<i>m</i>-pyridyl)Āurea, <b>L</b>, with
a variety of <i>cis</i>-protected palladiumĀ(II) components,
PdĀ(NāN)Ā(X)<sub>2</sub>. The <i>cis</i>-protecting
units āNāNā employed for the synthesis of <b>1</b>ā<b>4</b> are ethylenediamine (en), tetramethylethylenediamine
(tmeda), 2,2ā²-bipyridine (bpy), and 1,10-phenanthroline (phen),
respectively. The term āXā stands for nitrate and perchlorate
for <b>a</b> and <b>b</b>, respectively. The assemblies
are characterized by NMR and electrospray ionization mass spectrometry
(ESI-MS) techniques, and in some cases (i.e., <b>1a</b>,<b> 2b</b>,<b> 3b</b>,<b> 4a</b>, and <b>4b</b>) the structures are confirmed by single crystal X-ray diffraction.
The conformations of bound <b>L</b> in the crystal structures
of all the PdĀ(II) complexes are found to be <i>syn-syn</i>. The influence of the presence and absence of Ļ cloud at the <i>cis-</i>protecting units on the crystal packing has been studied
in detail. In the packing of [Pd<sub>2</sub>(phen)<sub>2</sub><b>L</b><sub>2</sub>]Ā(NO<sub>3</sub>)<sub>4</sub>, <b>4a</b>, one unit of [Pd<sub>2</sub>(phen)<sub>2</sub><b>L</b><sub>2</sub>]<sup>4+</sup> is associated with two other units by ĻāĻ
stacking interactions thus giving a one-dimensional growth as envisioned
on the basis of a design principle. In the case of [Pd<sub>2</sub>(en)<sub>2</sub>(<b>L)</b><sub>2</sub>]Ā(NO<sub>3</sub>)<sub>4</sub>, <b>1a</b>, and [Pd<sub>2</sub>(tmeda)<sub>2</sub>(<b>L</b>)<sub>2</sub>]Ā(ClO<sub>4</sub>)<sub>4</sub>, <b>2b</b>, such packing is not observed due to the absence of Ļ-cloud
at the strategic locations, instead notable H-bonding interactions
are seen. However, [Pd<sub>2</sub>(bpy)<sub>2</sub>(<b>L</b>)<sub>2</sub>]Ā(ClO<sub>4</sub>)<sub>4</sub>, <b>3b</b>, displays
a ĻāĻ interactions using only two units of [Pd<sub>2</sub>(bpy)<sub>2</sub>(<b>L</b>)<sub>2</sub>]<sup>4+</sup>(ClO<sub>4</sub>)<sup>ā</sup>
Consequence of Presence and Absence of ĻāClouds at Strategic Locations of Designed Binuclear Pd(II) Complexes on Packing: Self-Assembly of Self-Assembly by Intermolecular Locking and Packing
Self-assembled binuclear coordination cages of general
formula
[Pd<sub>2</sub>(NāN)<sub>2</sub>(<b>L</b>)<sub>2</sub>]Ā(X)<sub>4</sub>, <b>1a/b</b>ā<b>4a/b</b> are
prepared by the combination of <i>N</i>,<i>N</i>ā²-bisĀ(<i>m</i>-pyridyl)Āurea, <b>L</b>, with
a variety of <i>cis</i>-protected palladiumĀ(II) components,
PdĀ(NāN)Ā(X)<sub>2</sub>. The <i>cis</i>-protecting
units āNāNā employed for the synthesis of <b>1</b>ā<b>4</b> are ethylenediamine (en), tetramethylethylenediamine
(tmeda), 2,2ā²-bipyridine (bpy), and 1,10-phenanthroline (phen),
respectively. The term āXā stands for nitrate and perchlorate
for <b>a</b> and <b>b</b>, respectively. The assemblies
are characterized by NMR and electrospray ionization mass spectrometry
(ESI-MS) techniques, and in some cases (i.e., <b>1a</b>,<b> 2b</b>,<b> 3b</b>,<b> 4a</b>, and <b>4b</b>) the structures are confirmed by single crystal X-ray diffraction.
The conformations of bound <b>L</b> in the crystal structures
of all the PdĀ(II) complexes are found to be <i>syn-syn</i>. The influence of the presence and absence of Ļ cloud at the <i>cis-</i>protecting units on the crystal packing has been studied
in detail. In the packing of [Pd<sub>2</sub>(phen)<sub>2</sub><b>L</b><sub>2</sub>]Ā(NO<sub>3</sub>)<sub>4</sub>, <b>4a</b>, one unit of [Pd<sub>2</sub>(phen)<sub>2</sub><b>L</b><sub>2</sub>]<sup>4+</sup> is associated with two other units by ĻāĻ
stacking interactions thus giving a one-dimensional growth as envisioned
on the basis of a design principle. In the case of [Pd<sub>2</sub>(en)<sub>2</sub>(<b>L)</b><sub>2</sub>]Ā(NO<sub>3</sub>)<sub>4</sub>, <b>1a</b>, and [Pd<sub>2</sub>(tmeda)<sub>2</sub>(<b>L</b>)<sub>2</sub>]Ā(ClO<sub>4</sub>)<sub>4</sub>, <b>2b</b>, such packing is not observed due to the absence of Ļ-cloud
at the strategic locations, instead notable H-bonding interactions
are seen. However, [Pd<sub>2</sub>(bpy)<sub>2</sub>(<b>L</b>)<sub>2</sub>]Ā(ClO<sub>4</sub>)<sub>4</sub>, <b>3b</b>, displays
a ĻāĻ interactions using only two units of [Pd<sub>2</sub>(bpy)<sub>2</sub>(<b>L</b>)<sub>2</sub>]<sup>4+</sup>(ClO<sub>4</sub>)<sup>ā</sup>
Consequence of Presence and Absence of ĻāClouds at Strategic Locations of Designed Binuclear Pd(II) Complexes on Packing: Self-Assembly of Self-Assembly by Intermolecular Locking and Packing
Self-assembled binuclear coordination cages of general
formula
[Pd<sub>2</sub>(NāN)<sub>2</sub>(<b>L</b>)<sub>2</sub>]Ā(X)<sub>4</sub>, <b>1a/b</b>ā<b>4a/b</b> are
prepared by the combination of <i>N</i>,<i>N</i>ā²-bisĀ(<i>m</i>-pyridyl)Āurea, <b>L</b>, with
a variety of <i>cis</i>-protected palladiumĀ(II) components,
PdĀ(NāN)Ā(X)<sub>2</sub>. The <i>cis</i>-protecting
units āNāNā employed for the synthesis of <b>1</b>ā<b>4</b> are ethylenediamine (en), tetramethylethylenediamine
(tmeda), 2,2ā²-bipyridine (bpy), and 1,10-phenanthroline (phen),
respectively. The term āXā stands for nitrate and perchlorate
for <b>a</b> and <b>b</b>, respectively. The assemblies
are characterized by NMR and electrospray ionization mass spectrometry
(ESI-MS) techniques, and in some cases (i.e., <b>1a</b>,<b> 2b</b>,<b> 3b</b>,<b> 4a</b>, and <b>4b</b>) the structures are confirmed by single crystal X-ray diffraction.
The conformations of bound <b>L</b> in the crystal structures
of all the PdĀ(II) complexes are found to be <i>syn-syn</i>. The influence of the presence and absence of Ļ cloud at the <i>cis-</i>protecting units on the crystal packing has been studied
in detail. In the packing of [Pd<sub>2</sub>(phen)<sub>2</sub><b>L</b><sub>2</sub>]Ā(NO<sub>3</sub>)<sub>4</sub>, <b>4a</b>, one unit of [Pd<sub>2</sub>(phen)<sub>2</sub><b>L</b><sub>2</sub>]<sup>4+</sup> is associated with two other units by ĻāĻ
stacking interactions thus giving a one-dimensional growth as envisioned
on the basis of a design principle. In the case of [Pd<sub>2</sub>(en)<sub>2</sub>(<b>L)</b><sub>2</sub>]Ā(NO<sub>3</sub>)<sub>4</sub>, <b>1a</b>, and [Pd<sub>2</sub>(tmeda)<sub>2</sub>(<b>L</b>)<sub>2</sub>]Ā(ClO<sub>4</sub>)<sub>4</sub>, <b>2b</b>, such packing is not observed due to the absence of Ļ-cloud
at the strategic locations, instead notable H-bonding interactions
are seen. However, [Pd<sub>2</sub>(bpy)<sub>2</sub>(<b>L</b>)<sub>2</sub>]Ā(ClO<sub>4</sub>)<sub>4</sub>, <b>3b</b>, displays
a ĻāĻ interactions using only two units of [Pd<sub>2</sub>(bpy)<sub>2</sub>(<b>L</b>)<sub>2</sub>]<sup>4+</sup>(ClO<sub>4</sub>)<sup>ā</sup>
Consequence of Presence and Absence of ĻāClouds at Strategic Locations of Designed Binuclear Pd(II) Complexes on Packing: Self-Assembly of Self-Assembly by Intermolecular Locking and Packing
Self-assembled binuclear coordination cages of general
formula
[Pd<sub>2</sub>(NāN)<sub>2</sub>(<b>L</b>)<sub>2</sub>]Ā(X)<sub>4</sub>, <b>1a/b</b>ā<b>4a/b</b> are
prepared by the combination of <i>N</i>,<i>N</i>ā²-bisĀ(<i>m</i>-pyridyl)Āurea, <b>L</b>, with
a variety of <i>cis</i>-protected palladiumĀ(II) components,
PdĀ(NāN)Ā(X)<sub>2</sub>. The <i>cis</i>-protecting
units āNāNā employed for the synthesis of <b>1</b>ā<b>4</b> are ethylenediamine (en), tetramethylethylenediamine
(tmeda), 2,2ā²-bipyridine (bpy), and 1,10-phenanthroline (phen),
respectively. The term āXā stands for nitrate and perchlorate
for <b>a</b> and <b>b</b>, respectively. The assemblies
are characterized by NMR and electrospray ionization mass spectrometry
(ESI-MS) techniques, and in some cases (i.e., <b>1a</b>,<b> 2b</b>,<b> 3b</b>,<b> 4a</b>, and <b>4b</b>) the structures are confirmed by single crystal X-ray diffraction.
The conformations of bound <b>L</b> in the crystal structures
of all the PdĀ(II) complexes are found to be <i>syn-syn</i>. The influence of the presence and absence of Ļ cloud at the <i>cis-</i>protecting units on the crystal packing has been studied
in detail. In the packing of [Pd<sub>2</sub>(phen)<sub>2</sub><b>L</b><sub>2</sub>]Ā(NO<sub>3</sub>)<sub>4</sub>, <b>4a</b>, one unit of [Pd<sub>2</sub>(phen)<sub>2</sub><b>L</b><sub>2</sub>]<sup>4+</sup> is associated with two other units by ĻāĻ
stacking interactions thus giving a one-dimensional growth as envisioned
on the basis of a design principle. In the case of [Pd<sub>2</sub>(en)<sub>2</sub>(<b>L)</b><sub>2</sub>]Ā(NO<sub>3</sub>)<sub>4</sub>, <b>1a</b>, and [Pd<sub>2</sub>(tmeda)<sub>2</sub>(<b>L</b>)<sub>2</sub>]Ā(ClO<sub>4</sub>)<sub>4</sub>, <b>2b</b>, such packing is not observed due to the absence of Ļ-cloud
at the strategic locations, instead notable H-bonding interactions
are seen. However, [Pd<sub>2</sub>(bpy)<sub>2</sub>(<b>L</b>)<sub>2</sub>]Ā(ClO<sub>4</sub>)<sub>4</sub>, <b>3b</b>, displays
a ĻāĻ interactions using only two units of [Pd<sub>2</sub>(bpy)<sub>2</sub>(<b>L</b>)<sub>2</sub>]<sup>4+</sup>(ClO<sub>4</sub>)<sup>ā</sup>
Consequence of Presence and Absence of ĻāClouds at Strategic Locations of Designed Binuclear Pd(II) Complexes on Packing: Self-Assembly of Self-Assembly by Intermolecular Locking and Packing
Self-assembled binuclear coordination cages of general
formula
[Pd<sub>2</sub>(NāN)<sub>2</sub>(<b>L</b>)<sub>2</sub>]Ā(X)<sub>4</sub>, <b>1a/b</b>ā<b>4a/b</b> are
prepared by the combination of <i>N</i>,<i>N</i>ā²-bisĀ(<i>m</i>-pyridyl)Āurea, <b>L</b>, with
a variety of <i>cis</i>-protected palladiumĀ(II) components,
PdĀ(NāN)Ā(X)<sub>2</sub>. The <i>cis</i>-protecting
units āNāNā employed for the synthesis of <b>1</b>ā<b>4</b> are ethylenediamine (en), tetramethylethylenediamine
(tmeda), 2,2ā²-bipyridine (bpy), and 1,10-phenanthroline (phen),
respectively. The term āXā stands for nitrate and perchlorate
for <b>a</b> and <b>b</b>, respectively. The assemblies
are characterized by NMR and electrospray ionization mass spectrometry
(ESI-MS) techniques, and in some cases (i.e., <b>1a</b>,<b> 2b</b>,<b> 3b</b>,<b> 4a</b>, and <b>4b</b>) the structures are confirmed by single crystal X-ray diffraction.
The conformations of bound <b>L</b> in the crystal structures
of all the PdĀ(II) complexes are found to be <i>syn-syn</i>. The influence of the presence and absence of Ļ cloud at the <i>cis-</i>protecting units on the crystal packing has been studied
in detail. In the packing of [Pd<sub>2</sub>(phen)<sub>2</sub><b>L</b><sub>2</sub>]Ā(NO<sub>3</sub>)<sub>4</sub>, <b>4a</b>, one unit of [Pd<sub>2</sub>(phen)<sub>2</sub><b>L</b><sub>2</sub>]<sup>4+</sup> is associated with two other units by ĻāĻ
stacking interactions thus giving a one-dimensional growth as envisioned
on the basis of a design principle. In the case of [Pd<sub>2</sub>(en)<sub>2</sub>(<b>L)</b><sub>2</sub>]Ā(NO<sub>3</sub>)<sub>4</sub>, <b>1a</b>, and [Pd<sub>2</sub>(tmeda)<sub>2</sub>(<b>L</b>)<sub>2</sub>]Ā(ClO<sub>4</sub>)<sub>4</sub>, <b>2b</b>, such packing is not observed due to the absence of Ļ-cloud
at the strategic locations, instead notable H-bonding interactions
are seen. However, [Pd<sub>2</sub>(bpy)<sub>2</sub>(<b>L</b>)<sub>2</sub>]Ā(ClO<sub>4</sub>)<sub>4</sub>, <b>3b</b>, displays
a ĻāĻ interactions using only two units of [Pd<sub>2</sub>(bpy)<sub>2</sub>(<b>L</b>)<sub>2</sub>]<sup>4+</sup>(ClO<sub>4</sub>)<sup>ā</sup>