Cover Picture: Stable Luminescent [Cu(NN)(PP)]⁺ Complexes Incorporating a β‐Cyclodextrin‐Based Diphosphane Ligand with Metal‐Confining Properties (Angew. Chem. Int. Ed. 6/2023)

Stabilization of Luminescent Mononuclear Three‐Coordinate CuI Complexes by Two Distinct Cavity‐Shaped Diphosphanes Obtained from a Single α‐Cyclodextrin Precursor

“…Diphosphane 1 a was synthesized in a fashion similar to that for the β-CD analog 3 a. [7] The synthesis takes advantage of a Smiles-like rearrangement of diphenyl(2phosphanylphenyl)phosphane (4) in the presence of excess n-BuLi. The 1 : 1 mixture of the two resulting diastereomeric dianions 5 a,b (Scheme 1) was reacted with α-CD-derived dimesylate 6 a in THF to afford diphosphane-capped CDs as a 6 : 4 mixture consisting of, respectively, the desired confining cis diphosphane 1 a (Scheme 2) and its two trans diastereomers 1 b,c (Figure S2).…”

“…Recently, we have demonstrated that a cavity-shaped ligand in which a 1,2-bis(phenylphosphanyl)benzene unit is embedded in a permethylated β-CD unit, can enhance the luminescent properties of a tetrahedral [Cu(NN)(PP)] + complex by limiting the coordination sphere distortion of the excited state. [7] In the present article, we describe two diphosphanes (1 a and 2) with distinct inner-cavity environments derived from the smaller α-CD that can be elegantly synthesized from the same starting materials using slightly different reaction conditions. We then demonstrate their ability to form exclusively mononuclear trigonal [CuX(PP)] complexes by ensuring that the CuX unit (X = halide anion) remains inside the CD cavity.…”

Syntheses, characterization, crystal structures and applications as sensitizers in solar cells of novel heteroleptic Cu(i) complexes containing nitrile-substituted 2,2′-bipyridyl ligands

“…The λ em of ( 2 ) is red shifted with respect to ( 1 ) in 0.04 eV at 77 K and 0.06 eV at 298 K, as shown in Table 4, with similar Stokes shifts in both cases, higher than similar heteroleptic phosphine Cu( i ) complexes. 30,49…”

“…The λ em of (2) is red shifted with respect to (1) in 0.04 eV at 77 K and 0.06 eV at 298 K, as shown in Table 4, with similar Stokes shifts in both cases, higher than similar heteroleptic phosphine Cu(I) complexes. 30,49 The emission in the solid state of both complexes points to their applications as components of novel LEDs.…”

Heteroleptic copper(i) complexes with coumarin-substituted aminodiphosphine and diimine ligands: synthesis and photophysical studies

“…7,8 It has been well established in the literature that in comparison with related homoleptic structures, a combination of phosphine and diimine ligands may lead to stabilization of the excited state geometry (decreasing flattening distortion due to the oxidation of Cu(I) to Cu(II)) and thereby to enhanced PL properties. [9][10][11][12] After the isolation of the first heteroleptic copper complex by Buckner and McMillin in 1978, a wide variety of substituted diimine and diphosphine ligands have been investigated in order to tune the characteristics of the excited states and the resulting PL, which can proceed as fluorescence, phosphorescence or thermally activated delayed fluorescence. [13][14][15] It has been shown that these characteristics can be significantly modulated by a relatively moderate change in the substitution patterns of the coordinating ligands.…”