Kristallstruktur und schwingungsspektrometrische Daten von cis‐Na₂[Pd(SO₃)₂en] · 4 H₂O

Abstract

Die Verbindung cis‐Na2[Pd(SO3)2en] · 4 H2O (en = 1,2‐Diaminoethan) kristallisiert orthorhombisch in der Raumgruppe Pnma mit a = 623,7(2), b = 1070,9(10), c = 1989,5(30) pm und Z = 4. In den [Pd(SO3)2en]2−‐Anionen manifestiert sich der trans‐Einfluß der Sulfitliganden in langen PdN‐Bindungen bei kurzen PdS‐Abständen. Ein Satz von Na+‐Ionen liegt in flächenverknüpften Oktaedern Na(OH2)6+ vor, die Stäbe ∞1[Na(OH2)6/2]+ parallel [100] bilden. Ein zweiter Satz von Na+‐Ionen koordiniert zwei H2O‐Moleküle und vier O‐Atome aus SO3‐Liganden zweier Anionen ebenfalls zu Oktaedern mit Flächenverknüpfung; es resultieren Stäbe ∞1[Na(OH2)2/2{(OSO2)2Pd en}2/2]− parallel [100]. Die gegenüber Vergleichsdaten erniedrigten v(PdN) Frequenzen offenbaren den trans‐Einfluß der Sulfitliganden auch in den Schwingungsspektren.

Transformation of sulfur dioxide to sulfate at a palladium centre

“…7 Previously crystallographically characterised palladium sulfite complexes appear to be limited to cis-Na 2 [Pd(SO 3 ) 2 (en)] which also contains an S-bound SO 3 (Pd-S, 2.269; S-O ave , 1.484 A; O-S-O ave , 108.5Њ). 8 The similarity of these values to 1 is consistent with its formulation as a sulfite rather than a sulfur trioxide complex. In particular, no evidence for the presence of any O-bound protons could be found in the residual electron density surrounding the SO 3 ligand.…”

Structural Investigations of Sulfite-Bridged Binuclear Complexes of Platinum(II) and Palladium(II)

“…As expected, the Pd−S bond in 2 is clearly shorter [2.229(1) Å] than that in the complex Na 2 [Pd(SO 3 ) 2 (en)]·4 H 2 O [2.269(1) Å],11 involving monodentate S ‐coordinated sulfite ligands in an anionic complex species. After the bond‐valence approach,12 weakening of one bond causes an increase of the bond orders and hence the decrease of the bond lengths in adjacent bonds.…”

“…The Pd−N(2) bond [2.019(4) Å] is significantly shorter than Pd−N(1) bond [2.079(4) Å]. It is also shorter than the analogous Pd−N bonds in Na 2 [Pd(SO 3 ) 2 en] · 4 H 2 O [2.084(2) Å] 11. Both these examples serve to emphasise the effect of the trans ‐influence of the sulfite ligands, albeit to a different extent (dependent on the total charge and coordination mode).…”

A Palladium-Containing Polyoxotungstate with Anisotropic Proton Conductivity

“…To the best of our knowledge, 1 represents the first reported structure where Pd−S bonds are introduced into POMs. To date, there is only one example in which SO 3 2− is attached to Pd, and in that example, the other end of Pd is coordinated to N. 32 The Pd−S bond length is 2.269(1) Å, and the S−Pd−S angle is 97.40(3)°, which is essentially the same as in our structure. It is noteworthy that during the optimization of reaction conditions, the removal of sodium bisulfite from the reaction mixture can not lead to the formation of 1.…”

“…To the best of our knowledge, 1 represents the first reported structure where Pd–S bonds are introduced into POMs. To date, there is only one example in which SO 3 2– is attached to Pd, and in that example, the other end of Pd is coordinated to N . The Pd–S bond length is 2.269(1) Å, and the S–Pd–S angle is 97.40(3)°, which is essentially the same as in our structure.…”