Über Verbindungen subvalenter Hauptgruppenmetallkationen mit Dithiolaten, 3. Mitteilung [1]. Die Kristallstruktur von [As(C₆H₅)₄]₂[Pb(S₂C=C(CN)₂)₂]/Compounds of Subvalent Main Group Metal Cations with Dithiolates, Part 3 [1] Crystal Structure of [As(C₆H₅)₄]₂[Pb(S₂C=C(CN)₂)₂]

Abstract

The crystal structure of [AsPh4]2[Pb(S2C=C(CN)2)2] has been determined by X-ray diffraction. In the pyramidal complex anion [Pb(S2C=C(CN)2)2]2- Pb is coordinated to the sulfur atoms of the dithiolates. The geometry is indicative for a stereochemically active lone-pair at the apex of the square pyramid.

Structural Diversity of Iso-Maleonitrile Dithiolate d10s2 Metal Complexes of Lead and Bismuth

“…The structure of ( n Pr 4 N) 4 [Pb 2 ( i -mnt) 4 ] can be compared to the related (Ph 4 As) 4 [Pb 2 ( i -mnt) 4 ] dimer, , with the main difference that in (Ph 4 As) 4 [Pb 2 ( i -mnt) 4 ], each Pb­(II) center is described as six-coordinate, with all six sulfur atoms within the sum of the van der Waals radii (2.704–3.597 Å), , i.e., both S3 and S4 donors in the μ- i -mnt ligands show bridging interactions between both Pb­(II) centers, while in ( n Pr 4 N) 4 [Pb 2 ( i -mnt) 4 ] the S4 donor does not bridge (Pb1–S4 = 4.833(1) Å). Other dimeric metal-bridging μ- i -mnt motifs have been previously reported, including a zinc­(II) complex with two μ- i -mnt ligands bridging two ZnL 2 units (L = 4-methylpyridine, 1,3-diaminopropane) , and the dimeric Hg 2 ( i -mnt) 4 .…”

“…30−35 This tunable structural feature may introduce an element of noncentrosymmetry, which is often leveraged to engineer materials with functional properties such as piezo/pyroelectricity and nonlinear optical behavior. 36−40 There are currently 166 structurally characterized S-bound metal i-mnt complexes (Cambridge Structural Database, accessed 22 February 2024), 41 43,44 and a pair of [K(18-crown-6)] 2 [Pb(i-mnt) 2 ] CPs, where the N-cyano groups bind to the potassium cation. 45 Of particular interest is K 2 [Pb(i-mnt) 2 ], which forms a 1D chain, crystallizing in the polar C2 space group and featuring a stereochemically active lone pair on the Pb(II) center.…”

“…Comparatively, there are very few i -mnt-containing structures incorporating p-block metals, and none include bismuth. In fact, the only complexes with d 10 s 2 ions reported are those with Pb­(II) centers, including two polymorphs of [Pb­( i -mnt)] 2 , the dinuclear [Ph 4 As] 4 [Pb 2 ( i -mnt) 4 ], , and a pair of [K­(18-crown-6)] 2 [Pb­( i -mnt) 2 ] CPs, where the N-cyano groups bind to the potassium cation . Of particular interest is K 2 [Pb­( i -mnt) 2 ], which forms a 1D chain, crystallizing in the polar C2 space group and featuring a stereochemically active lone pair on the Pb­(II) center .…”