Consequence of Presence and Absence of π‑Clouds 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 [Pd₂(N–N)₂(<b>L</b>)₂]­(X)₄, <b>1a/b</b>–<b>4a/b</b> are prepared by the combination of <i>N</i>,<i>N</i>′-bis­(<i>m</i>-pyridyl)­urea, <b>L</b>, with a variety of <i>cis</i>-protected palladium­(II) components, Pd­(N–N)­(X)₂. The <i>cis</i>-protecting units “N–N” employed for the synthesis of <b>1</b>–<b>4</b> are ethylenediamine (en), tetramethylethylenediamine (tmeda), 2,2′-bipyridine (bpy), and 1,10-phenanthroline (phen), respectively. The term “X” 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 Pd­(II) complexes are found to be <i>syn-syn</i>. The influence of the presence and absence of π cloud at the <i>cis-</i>protecting units on the crystal packing has been studied in detail. In the packing of [Pd₂(phen)₂<b>L</b>₂]­(NO₃)₄, <b>4a</b>, one unit of [Pd₂(phen)₂<b>L</b>₂]⁴⁺ is associated with two other units by π–π stacking interactions thus giving a one-dimensional growth as envisioned on the basis of a design principle. In the case of [Pd₂(en)₂(<b>L)</b>₂]­(NO₃)₄, <b>1a</b>, and [Pd₂(tmeda)₂(<b>L</b>)₂]­(ClO₄)₄, <b>2b</b>, such packing is not observed due to the absence of π-cloud at the strategic locations, instead notable H-bonding interactions are seen. However, [Pd₂(bpy)₂(<b>L</b>)₂]­(ClO₄)₄, <b>3b</b>, displays a π–π interactions using only two units of [Pd₂(bpy)₂(<b>L</b>)₂]⁴⁺(ClO₄)⁻

Consequence of Presence and Absence of π‑Clouds 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 [Pd₂(N–N)₂(<b>L</b>)₂]­(X)₄, <b>1a/b</b>–<b>4a/b</b> are prepared by the combination of <i>N</i>,<i>N</i>′-bis­(<i>m</i>-pyridyl)­urea, <b>L</b>, with a variety of <i>cis</i>-protected palladium­(II) components, Pd­(N–N)­(X)₂. The <i>cis</i>-protecting units “N–N” employed for the synthesis of <b>1</b>–<b>4</b> are ethylenediamine (en), tetramethylethylenediamine (tmeda), 2,2′-bipyridine (bpy), and 1,10-phenanthroline (phen), respectively. The term “X” 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 Pd­(II) complexes are found to be <i>syn-syn</i>. The influence of the presence and absence of π cloud at the <i>cis-</i>protecting units on the crystal packing has been studied in detail. In the packing of [Pd₂(phen)₂<b>L</b>₂]­(NO₃)₄, <b>4a</b>, one unit of [Pd₂(phen)₂<b>L</b>₂]⁴⁺ is associated with two other units by π–π stacking interactions thus giving a one-dimensional growth as envisioned on the basis of a design principle. In the case of [Pd₂(en)₂(<b>L)</b>₂]­(NO₃)₄, <b>1a</b>, and [Pd₂(tmeda)₂(<b>L</b>)₂]­(ClO₄)₄, <b>2b</b>, such packing is not observed due to the absence of π-cloud at the strategic locations, instead notable H-bonding interactions are seen. However, [Pd₂(bpy)₂(<b>L</b>)₂]­(ClO₄)₄, <b>3b</b>, displays a π–π interactions using only two units of [Pd₂(bpy)₂(<b>L</b>)₂]⁴⁺(ClO₄)⁻

Consequence of Presence and Absence of π‑Clouds 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 [Pd₂(N–N)₂(<b>L</b>)₂]­(X)₄, <b>1a/b</b>–<b>4a/b</b> are prepared by the combination of <i>N</i>,<i>N</i>′-bis­(<i>m</i>-pyridyl)­urea, <b>L</b>, with a variety of <i>cis</i>-protected palladium­(II) components, Pd­(N–N)­(X)₂. The <i>cis</i>-protecting units “N–N” employed for the synthesis of <b>1</b>–<b>4</b> are ethylenediamine (en), tetramethylethylenediamine (tmeda), 2,2′-bipyridine (bpy), and 1,10-phenanthroline (phen), respectively. The term “X” 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 Pd­(II) complexes are found to be <i>syn-syn</i>. The influence of the presence and absence of π cloud at the <i>cis-</i>protecting units on the crystal packing has been studied in detail. In the packing of [Pd₂(phen)₂<b>L</b>₂]­(NO₃)₄, <b>4a</b>, one unit of [Pd₂(phen)₂<b>L</b>₂]⁴⁺ is associated with two other units by π–π stacking interactions thus giving a one-dimensional growth as envisioned on the basis of a design principle. In the case of [Pd₂(en)₂(<b>L)</b>₂]­(NO₃)₄, <b>1a</b>, and [Pd₂(tmeda)₂(<b>L</b>)₂]­(ClO₄)₄, <b>2b</b>, such packing is not observed due to the absence of π-cloud at the strategic locations, instead notable H-bonding interactions are seen. However, [Pd₂(bpy)₂(<b>L</b>)₂]­(ClO₄)₄, <b>3b</b>, displays a π–π interactions using only two units of [Pd₂(bpy)₂(<b>L</b>)₂]⁴⁺(ClO₄)⁻

Consequence of Presence and Absence of π‑Clouds 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 [Pd₂(N–N)₂(<b>L</b>)₂]­(X)₄, <b>1a/b</b>–<b>4a/b</b> are prepared by the combination of <i>N</i>,<i>N</i>′-bis­(<i>m</i>-pyridyl)­urea, <b>L</b>, with a variety of <i>cis</i>-protected palladium­(II) components, Pd­(N–N)­(X)₂. The <i>cis</i>-protecting units “N–N” employed for the synthesis of <b>1</b>–<b>4</b> are ethylenediamine (en), tetramethylethylenediamine (tmeda), 2,2′-bipyridine (bpy), and 1,10-phenanthroline (phen), respectively. The term “X” 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 Pd­(II) complexes are found to be <i>syn-syn</i>. The influence of the presence and absence of π cloud at the <i>cis-</i>protecting units on the crystal packing has been studied in detail. In the packing of [Pd₂(phen)₂<b>L</b>₂]­(NO₃)₄, <b>4a</b>, one unit of [Pd₂(phen)₂<b>L</b>₂]⁴⁺ is associated with two other units by π–π stacking interactions thus giving a one-dimensional growth as envisioned on the basis of a design principle. In the case of [Pd₂(en)₂(<b>L)</b>₂]­(NO₃)₄, <b>1a</b>, and [Pd₂(tmeda)₂(<b>L</b>)₂]­(ClO₄)₄, <b>2b</b>, such packing is not observed due to the absence of π-cloud at the strategic locations, instead notable H-bonding interactions are seen. However, [Pd₂(bpy)₂(<b>L</b>)₂]­(ClO₄)₄, <b>3b</b>, displays a π–π interactions using only two units of [Pd₂(bpy)₂(<b>L</b>)₂]⁴⁺(ClO₄)⁻

Consequence of Presence and Absence of π‑Clouds 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 [Pd₂(N–N)₂(<b>L</b>)₂]­(X)₄, <b>1a/b</b>–<b>4a/b</b> are prepared by the combination of <i>N</i>,<i>N</i>′-bis­(<i>m</i>-pyridyl)­urea, <b>L</b>, with a variety of <i>cis</i>-protected palladium­(II) components, Pd­(N–N)­(X)₂. The <i>cis</i>-protecting units “N–N” employed for the synthesis of <b>1</b>–<b>4</b> are ethylenediamine (en), tetramethylethylenediamine (tmeda), 2,2′-bipyridine (bpy), and 1,10-phenanthroline (phen), respectively. The term “X” 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 Pd­(II) complexes are found to be <i>syn-syn</i>. The influence of the presence and absence of π cloud at the <i>cis-</i>protecting units on the crystal packing has been studied in detail. In the packing of [Pd₂(phen)₂<b>L</b>₂]­(NO₃)₄, <b>4a</b>, one unit of [Pd₂(phen)₂<b>L</b>₂]⁴⁺ is associated with two other units by π–π stacking interactions thus giving a one-dimensional growth as envisioned on the basis of a design principle. In the case of [Pd₂(en)₂(<b>L)</b>₂]­(NO₃)₄, <b>1a</b>, and [Pd₂(tmeda)₂(<b>L</b>)₂]­(ClO₄)₄, <b>2b</b>, such packing is not observed due to the absence of π-cloud at the strategic locations, instead notable H-bonding interactions are seen. However, [Pd₂(bpy)₂(<b>L</b>)₂]­(ClO₄)₄, <b>3b</b>, displays a π–π interactions using only two units of [Pd₂(bpy)₂(<b>L</b>)₂]⁴⁺(ClO₄)⁻

Consequence of Presence and Absence of π‑Clouds 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 [Pd₂(N–N)₂(<b>L</b>)₂]­(X)₄, <b>1a/b</b>–<b>4a/b</b> are prepared by the combination of <i>N</i>,<i>N</i>′-bis­(<i>m</i>-pyridyl)­urea, <b>L</b>, with a variety of <i>cis</i>-protected palladium­(II) components, Pd­(N–N)­(X)₂. The <i>cis</i>-protecting units “N–N” employed for the synthesis of <b>1</b>–<b>4</b> are ethylenediamine (en), tetramethylethylenediamine (tmeda), 2,2′-bipyridine (bpy), and 1,10-phenanthroline (phen), respectively. The term “X” 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 Pd­(II) complexes are found to be <i>syn-syn</i>. The influence of the presence and absence of π cloud at the <i>cis-</i>protecting units on the crystal packing has been studied in detail. In the packing of [Pd₂(phen)₂<b>L</b>₂]­(NO₃)₄, <b>4a</b>, one unit of [Pd₂(phen)₂<b>L</b>₂]⁴⁺ is associated with two other units by π–π stacking interactions thus giving a one-dimensional growth as envisioned on the basis of a design principle. In the case of [Pd₂(en)₂(<b>L)</b>₂]­(NO₃)₄, <b>1a</b>, and [Pd₂(tmeda)₂(<b>L</b>)₂]­(ClO₄)₄, <b>2b</b>, such packing is not observed due to the absence of π-cloud at the strategic locations, instead notable H-bonding interactions are seen. However, [Pd₂(bpy)₂(<b>L</b>)₂]­(ClO₄)₄, <b>3b</b>, displays a π–π interactions using only two units of [Pd₂(bpy)₂(<b>L</b>)₂]⁴⁺(ClO₄)⁻

Consequence of Presence and Absence of π‑Clouds 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 [Pd₂(N–N)₂(<b>L</b>)₂]­(X)₄, <b>1a/b</b>–<b>4a/b</b> are prepared by the combination of <i>N</i>,<i>N</i>′-bis­(<i>m</i>-pyridyl)­urea, <b>L</b>, with a variety of <i>cis</i>-protected palladium­(II) components, Pd­(N–N)­(X)₂. The <i>cis</i>-protecting units “N–N” employed for the synthesis of <b>1</b>–<b>4</b> are ethylenediamine (en), tetramethylethylenediamine (tmeda), 2,2′-bipyridine (bpy), and 1,10-phenanthroline (phen), respectively. The term “X” 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 Pd­(II) complexes are found to be <i>syn-syn</i>. The influence of the presence and absence of π cloud at the <i>cis-</i>protecting units on the crystal packing has been studied in detail. In the packing of [Pd₂(phen)₂<b>L</b>₂]­(NO₃)₄, <b>4a</b>, one unit of [Pd₂(phen)₂<b>L</b>₂]⁴⁺ is associated with two other units by π–π stacking interactions thus giving a one-dimensional growth as envisioned on the basis of a design principle. In the case of [Pd₂(en)₂(<b>L)</b>₂]­(NO₃)₄, <b>1a</b>, and [Pd₂(tmeda)₂(<b>L</b>)₂]­(ClO₄)₄, <b>2b</b>, such packing is not observed due to the absence of π-cloud at the strategic locations, instead notable H-bonding interactions are seen. However, [Pd₂(bpy)₂(<b>L</b>)₂]­(ClO₄)₄, <b>3b</b>, displays a π–π interactions using only two units of [Pd₂(bpy)₂(<b>L</b>)₂]⁴⁺(ClO₄)⁻