Ligand-controlled Behavior of Ag(I)–π Complex as σ-Lewis Acid

Abstract

An efficient σ-Lewis acidic Ag(I) complex has been obtained by complexation with an electron-donating π-conjugated molecule as a side-on π ligand. The σ-Lewis acidity is possibly derived from the controlled linear coordination around Ag(I) due to the π ligand. A combination of UV-Vis absorption spectroscopy and X-ray absorption near-edge structure analyses clearly revealed that the complex is formed by π ligand-to-Ag(I) charge-transfer interaction. The σ-Lewis acidity was evaluated by IR spectroscopy using 2,6-dimethyl-γ-pyrone as the σ-Lewis basic molecule.

Halogen Transfer to Carbon Radicals by High-Valent Iron Chloride and Iron Fluoride Corroles

“…A second OTf – anion coordinates to the Ag I , completing its coordination sphere. The Ag–C β distances of 2.55(2) and 2.46(2) Å are similar to what has been seen for Ag–C β interactions (2.44, 2.48 Å) in a Ni II porphyrin complex from XANES and DFT analysis . There are also relatively close contacts (2.55(2)–2.62(2) Å and 2.53(2)–2.57(2) Å) between the Ag I ion and two of the carbon atoms on each of the adjacent phenyl rings, similar to other η 2 –π interactions seen for the Ag I ion and benzene derivatives .…”

“…The Ag−C β distances of 2.55(2) and 2.46(2) Å are similar to what has been seen for Ag−C β interactions (2.44, 2.48 Å) in a Ni II porphyrin complex from XANES and DFT analysis. 70 There Scheme 3. Synthesis of Complex 2 S5).…”

Ag(I)-π interactions with pyrrolic derivatives

“…Recently, Ag-π interactions have been used to modify the σ-Lewis acidity of catalysts to allow the activation of ketones and aldehydes [37]. Whereas silver-based π-Lewis acid catalysts have been largely explored [38], their use as σ-Lewis acid catalysts is less common.…”

“…3. Modulation of the σ-Lewis acidity of Ag(I) center for interaction with ketones using πcomplexing Ni(II) porphyrin 7, as proposed in [37].…”

Infusion of Variable Chemical Structure to Tune Stacking among Metal‐Organic Layers in 2D Nano MOF

“…One of the most probable reason in case of pillar is the Zn(II)-bpy bond is much stronger than Zn(II)-DABCO bond because in the former case the corresponding bond gets partial double bond character due to the fact that bpy is π-lewis acidic ligand whereas DABCO is not. [45] Such variable stacking efficiency of 2D stacked sheets as shown in various experimental observations as discussed above might also be correlated to the nature of parent frameworks, which largely depends on nature of organic linker used in it. Some previous reports showed the formation of single MOL/multi MOLs by exfoliation of pillar linker but understanding of such MOLs stacking which might guide to get thickness modulation mechanism of 2D MOFs was lacking (Table 2 of SI).…”