Molecular Alignment of Alkynylplatinum(II) 2,6-Bis(benzimidazol-2-yl)pyridine Double Complex Salts and the Formation of Well-Ordered Nanostructures Directed by Pt···Pt and Donor–Acceptor Interactions

Abstract

A new class of alkynylplatinum­(II) bzimpy (bzimpy = bis­(benzimidazol-2-yl)­pyridine) double complex salts (DCSs) containing dialkoxynaphthalene or pyromellitic diimide moieties on the alkynyl ligand has been reported to display distinct morphological properties compared to their precursor alkynylplatinum­(II) complexes, with the capability of being aligned by the directional Pt···Pt and/or π–π stacking interactions. The incorporation of donor and acceptor units on the alkynyl ligands has been found to significantly perturb the alignment of the oppositely charged complex ions in the DCSs to stack in a twisted head-to-head manner, attributed to the additional driving forces of electrostatic and donor–acceptor interactions. The modulation of the Pt···Pt distances and the extent of aggregate formation have been demonstrated by altering the charge matching between the platinum­(II) bzimpy moieties and the donor or acceptor moieties on the alkynyl ligand.

Blue Iridium (III) Phosphorescent OLEDs with High Brightness Over 10 000 cd m−2 and Ultralow Efficiency Roll‐Off

“…However, complexes 4 and 6 exhibited a red‐shifted emission and complex 3 showed a vibronic‐structural emission spectra, indicating that the polarity of the solvent and the molecular packing styles in the solid condition may also affect the emissive state and in turn the emission spectra. [ 38,43,49,50 ] Specifically, complexes 3 and 6 exhibit almost unity internal quantum efficiency with short excited state lifetime value down to 1 µs in the 10 wt% doping in co‐host (mCBP: B4PymPm = 1:1) thin‐film, indicating a high k r of up to 10 6 s −1 (see Figure 2d and Table 2), highly comparable to the most advanced iridium(III), [ 51–55 ] platinum(II), [ 56–58 ] and TADF‐gold(III) emitters. [ 59–61 ] Such observations suggested that the short‐excited state properties of the complexes are also beneficial to reduce the annihilation process due to the rapid radiative decay.…”

Photoresponsive Rotaxane-Branched Dendrimers: From Nanoscale Dimension Modulation to Macroscopic Soft Actuators

“…With the [2]­rotaxane Azo-R as the key precursor in hand, a controllable divergent strategy was employed for the synthesis of the targeted rotaxane-branched dendrimers incorporating individual photoresponsive mechanically interlocked unit precisely arranged on each branches. As shown in Figure , the formation of platinum-acetylide bonds is the key to each growth step . The first generation photoresponsive rotaxane-branched dendrimer AG1 with three photoresponsive [2]­rotaxane units was successfully prepared by the Cu­(I)-catalyzed reaction of Azo-R and 1,3,5-triethynylbenzene in an excellent yield of 94%.…”

Supramolecular architectures based on binuclear Pt(ii) complexes consisting of different ligands and circular and helical fiber structures

“…35 Platinum(II) complexes of tridentate π-acceptor ligands are known to exhibit excellent spectroscopic properties and possess a high tendency to form supramolecular architectures by Pt⋯Pt and π-π interactions in the solid and solution states, owing to their square-planar structure. [36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51][52][53] Therefore, supramolecular architectures based on Pt(II) complexes have attracted much attention because of their intrinsically interesting physical properties and various morphologies of selfassembled architectures. For example, V. W.-W. Yam et al reported various morphologies of supramolecular aggregates based on mono-and binuclear platinum(II) complexes, such as helical fibers, and tubular and ribbon structures, and their spectroscopic properties.…”