Synthesis, photophysical and electrophosphorescent properties of mononuclear Pt(II) complexes with arylamine functionalized cyclometalating ligands

Synthesis, crystal structure and photophysical properties of a novel Pt(II) complex with multi-functionalized cyclometalating ligand

“…The bond distances of Pt-C(1), Pt-N(1) and Pt-N(2) are 2.021(4), 1.868 (3) and 2.082 (4) Å, respectively, which are comparable to those of previously reported analogous [21][22][23][24]. The configuration of C^N^N ligand is basically a plane with the C(1)-C(6)-C (7) [23,24] or a alternating arranged dimer [8], the complex molecules are stacked in a head-to-tail fashion along the b axis to form 1D chain (Fig. 2) with a Pt-Pt distance of 6.245 Å, suggesting no metal-metal interaction.…”

“…Our group [8] integrated hole-transporting arylamine into the [(C^N^N)Pt] phosphorescent emitting center to form a novel class of multifunctional complexes. The bathochromically shifted maxima in the absorption and emission spectra indicate that the incorporation of an electron-rich group into the electron-deficient pyridine moiety can strengthen the donor-acceptor (D-A) interaction.…”

“…The intense absorption bands in the high-energy region (λ b 376 nm) with extinction coefficients (ε) of the order of 10 4 dm 3 mol -1 cm -1 were observed in the absorption spectra of 3 and 4, which are dominated by 1 IL (π → π*) transitions, while the low-energy band with λ max at 448 nm in the absorption spectrum of 4 is assigned to the spinallowed singlet dπ(Pt) → π*(L) metal-to-ligand charge transfer ( 1 MLCT) transitions. Owing to the strong D-A interaction between the amine unit and the C^N^N cyclometalating ligand [8], the molar extinction coefficient of the MLCT band is 2-3 times larger than those of the reported C^N^N cyclometalated Pt(II) complexes [1,2]. Compared to that of the reported complex [(L 2 )PtCl], no apparent change in the long-wavelength region of the absorption spectrum was observed for 4, suggesting the introduction of carbazole unit through alkyl chain has no influence on the energy level of the [(L 2 )PtCl] moiety.…”

Synthesis, crystal structure, photophysical property and electropolymerization of Pt(II) complexes with carbazole-grafting 2-(2-pyridyl)benzimidazole

“…Carbazole and its derivatives are classic blue-emission and electroactive materials with high triplet energy level and good charge transport ability, widely utilized as hosters and charge transporters in OLEDs [17][18][19], conductive electropolymers [20,21], and electrochromic polymers [22]. However, integration of carbazole unit and the emissive [Pt(PB)(C≡CAr) 2 ] complex into a single molecule has so far never been reported yet.…”

Synthesis and photophysical properties of cyclometalated 4′-phenyl-2,2′:6′,2″-terpyridyl Pt(II) chloride complexes with different aryl substituents

“…To date, the widely investigated nonlinear optical materials are metallophthalocyanines [3], organic dendrimers [4,5], bis(styryl)benzene derivatives [6] and metalloporphyrins [7]. Besides these, cyclometalated Pt(II) complexes have attracted great interest in recent years due to their intriguing spectroscopic properties as well as potential applications in the fields of optoelectronic devices [8][9][10][11][12], photocatalysis [13][14][15], chemosensors [16,17] and nonlinear optics [18][19][20][21][22]. Their rich photophysical properties and applications are intrinsically based on the presence of multiple charge transfer excited states, such as metal-to-ligand charge transfer (MLCT), ligand-to-ligand charge transfer (LLCT), intraligand charge transfer (ILCT), in addition to the ligand localized π,π* transitions.…”