Synthesis, Electronic Properties and OLED Devices of Chromophores Based on λ⁵‐Phosphinines

Abstract

A new series of 2,4,6‐triaryl‐λ5‐phosphinines have been synthesized that contain different substituents both on the carbon backbone and the phosphorus atom of the six‐membered heterocycle. Their optical and redox properties were studied in detail, supported by in‐depth theoretical calculations. The modularity of the synthetic strategy allowed the establishment of structure–property relationships for this class of compounds and an OLED based on a blue phosphinine emitter could be developed for the first time.

Phosphorus Analogues of [Ni(bpy)2]: Synthesis and Application in Carbon–Halogen Bond Activation

“…Crystals of 2 were obtained by slow evaporation of the resulting fluorescent orange n -hexane solution. Single-crystal XRD revealed its identity as a 1,1-diphenyl-λ 5 -phosphinine (Figure ), which accounts for the observed fluorescent properties. − This structure formally arises from the addition of two phenyl groups to the P center of the phosphinine ligand L . As reported for other λ 5 -phosphinines, the P1–C1/C5 bonds are slightly shortened compared to P–C single bonds (mean distance 1.763 Å vs sum of covalent radii 1.86 Å), while the C–C bonds are in the range of CC double bonds (mean distance 1.395 Å vs sum of covalent radii 1.34 Å) .…”

“…This is in accordance with our expectations for the steric demand of the N lone pair, which is smaller than a CH group of a phenyl moiety. 76,78 The n-hexane-insoluble material remaining after separation of 2 could be dissolved in THF to give a red NMR-silent solution. Single crystals suitable for XRD were obtained after layering with n-hexane.…”

Straightforward access to multifunctional pi-conjugated P-heterocycles

“…ε [a] [M -1 cm -1 ] em(DCM) [a] () [b] [nm] em(C5) [c] () [b] [nm] In conclusion, a straightforward one-pot synthesis of 5 or 6-membered P-heterocycles featuring internal ylidic bond (P-containing acenaphthylenes and phenanthrenes) is presented (5)(6)(7)(8)(9). These -conjugated systems are easily obtained through intramolecular cyclization of ylides, generated from readily available phosphines.…”

“…The intense fluorescence of its -extended form, associated with remarkable chemical and thermal stability allowed using it as emitter in OLED or in organic laser (B, Fig 1). [8][9][10] [11] Regarding five-membered ring, limited reports describe the properties of λ 5 -phospholes or diphospha-acenes such C (Fig. 1).…”

Reversible Redox Chemistry of Anionic Imidazole-2-thione-Fused 1,4-Dihydro-1,4-diphosphinines

“… 8 So far, the redox chemistry of λ 5 -phosphinines III has been investigated for optovoltaic applications in the design of organic light-emitting diodes (OLEDs). 9 Similarly, P V -phospharhodamines have been extensively investigated for their photovoltaic applications. 10 All these six-membered phosphorus heterocycles, mostly dominated by the P V -phospholes, share anodic photovoltaic behavior largely centered in the unsaturated hydrocarbon portion of the molecules with the P(V) centers uninvolved in redox processes.…”