Recent advances in materials for organic light emitting diodes

• Eli Zysman-Colman

Beilstein J. Org. Chem. 2018, 14, 1944–1945, doi:10.3762/bjoc.14.168

• this thematic issue provide a window into the design principles used towards the development of next-generation emitter and host materials for OLEDs. I hope these articles will provide inspiration for further research in this exciting area. Eli Zysman-Colman St Andrews, June 2018 Eli Zysman-Colman

Recent advances in phosphorescent platinum complexes for organic light-emitting diodes

• Cristina Cebrián and
• Matteo Mauro

Beilstein J. Org. Chem. 2018, 14, 1459–1481, doi:10.3762/bjoc.14.124

• including photocatalysis [6], bio-imaging [7][8], and solar-energy conversion [9], just to cite a few. Thompson and Forrest reported in 1998 on the first example of a phosphorescent emitter, namely 2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphyrin platinum(II) (Pt(OEP)), used as dopant for the fabrication of

• concentration with an estimated LT97 = 2057 h and EQE = 15.3% at 1000 cd m−2. Seeking for stable and efficient blue emitter for OLED devices and following the previous work on the red-emissive compound 33 and the green-emissive derivative 36 that showed a peak EQE of 14.3% [83], Li and co-workers developed a

• -based counterpart. Upon device optimization, 37 resulted to be a rather efficient sky-blue triplet emitter. In particular, OLEDs with the following architecture ITO/HATCN (10 nm)/NPD (40 nm)/TrisPCz (10 nm)/complex 37 10 wt %:mCBP (25 nm)/mCBT (8 nm)/BPyTP (40 nm)/LiF (1 nm)/Al (100 nm) were fabricated

D–A–D-type orange-light emitting thermally activated delayed fluorescence (TADF) materials based on a fluorenone unit: simulation, photoluminescence and electroluminescence studies

• Lin Gan,
• Xianglong Li,
• Xinyi Cai,
• Kunkun Liu,
• Wei Li and
• Shi-Jian Su

Beilstein J. Org. Chem. 2018, 14, 672–681, doi:10.3762/bjoc.14.55

• % emitter in CBP (35 nm)/TmPyPB (55 nm)/LiF (1 nm)/Al, where 1,1-bis(4-(di-p-tolylamino)phenyl)cyclohexane (TAPC), 4,4'-bis(9H-carbazol-9-yl)biphenyl (CBP), 1,3,5-tri[(3-pyridyl)-phen-3-yl]benzene (TmPyPB) and LiF play the roles of hole transport layer, host material, electron transport layer and electron

• injection layer, respectively [22]. The energy level diagrams and the chemical structures of the materials utilized are shown in Figure 5. TAPC and TmPyPB also play the role of exciton blocking layer at the same time because of their high T1 energy level. Carriers will also be trapped by the emitter

• directly because of the energy level difference between CBP and the emitter, which makes it possible for the OLEDs with such a low emitter concentration to achieve complete energy transfer. The performance of the fabricated devices is summarized in Table 5 while the J–V–L (current density–voltage–luminance

Enhanced quantum yields by sterically demanding aryl-substituted β-diketonate ancillary ligands

• Rebecca Pittkowski and
• Thomas Strassner

Beilstein J. Org. Chem. 2018, 14, 664–671, doi:10.3762/bjoc.14.54

• complexes were measured on a Perkin Elmer lambda 25 spectrophotometer in dichloromethane solution. Photoluminescence measurements were performed in amorphous PMMA thin films doped with the emitter. Films were prepared by doctor blading a solution of 2 wt % emitter in a 10 wt % PMMA solution in

Recent advances on organic blue thermally activated delayed fluorescence (TADF) emitters for organic light-emitting diodes (OLEDs)

• Thanh-Tuân Bui,
• Fabrice Goubard,
• Malika Ibrahim-Ouali,
• Didier Gigmes and
• Frédéric Dumur

Beilstein J. Org. Chem. 2018, 14, 282–308, doi:10.3762/bjoc.14.18

• popularized by Chihaya Adachi since 2012. In this review, we proposed to focus on the recent advances in the molecular design of blue TADF emitters for OLEDs during the last few years. Keywords: blue; electroluminescence; emitter; OLED; TADF; Introduction Since the pioneering works of Tang and VanSlyke in

• the light-emitting ability of the emitter, which is directly related to the nature, and the photoluminescence quantum yield (PLQY) of the emitter. Based on spin statistics, upon electrical excitation, singlet and triplet excitons are formed in a 1:3 ratio [4]. In the case of fluorescent materials

• the fabrication of highly emissive blue OLEDs. Devices fabricated with D6 furnished a maximum EQE of 19.5% and maintained the high EQE of 16% at 1000 cd/m2 with a satisfactory color purity of coordinates (0.16, 0.20). Recently, high-performance TADF based hybrid WOLEDs employing D6 as the blue emitter

A postsynthetically 2’-“clickable” uridine with arabino configuration and its application for fluorescent labeling and imaging of DNA

• Heidi-Kristin Walter,
• Bettina Olshausen,
• Ute Schepers and
• Hans-Achim Wagenknecht

Beilstein J. Org. Chem. 2017, 13, 127–137, doi:10.3762/bjoc.13.16

• corresponding unmodified counterstrand. The four fluorophores D1 [23], a blue emitter excitable at 389 nm, D2 [24], D3 [19], and D4 [24], all green emitters excitable at 450–460 nm, that were “clicked” to the oligonucleotides DNA1a and DNA1r belong to our recently established class of cyanine-styryl dyes that

Bright molecules for sensing, computing and imaging: a tale of two once-troubled cities

• A. Prasanna de Silva

Beilstein J. Org. Chem. 2015, 11, 2774–2784, doi:10.3762/bjoc.11.298

• naturally harnesses the diversity available in each of the three modules. For instance, the lumophore could be a fluorescent dye [3][24], a room temperature phosphor [25][26], or a lanthanide-based emitter [27][28]. Colleagues showed that even a quantum dot [29] would fit the bill. The receptor could be an

Design, synthesis and photochemical properties of the first examples of iminosugar clusters based on fluorescent cores

• Mathieu L. Lepage,
• Antoine Mirloup,
• Manon Ripoll,
• Fabien Stauffert,
• Anne Bodlenner,
• Raymond Ziessel and
• Philippe Compain

Beilstein J. Org. Chem. 2015, 11, 659–667, doi:10.3762/bjoc.11.74

• of 24% (in aqueous glycine buffer at pH 10.7), the profile of the band mirrors the absorption with a maximum at 558 nm which is in keeping with little reorganization in the excited state and characteristic of a singlet emitter. The modest Stokes shift (Δss = 1020 cm−1) and the short excited state

Studies on the photodegradation of red, green and blue phosphorescent OLED emitters

• Susanna Schmidbauer,
• Andreas Hohenleutner and
• Burkhard König

Beilstein J. Org. Chem. 2013, 9, 2088–2096, doi:10.3762/bjoc.9.245

• photostabilities of the red and blue emitter and the solvent effect is therefore negligible. With the overall higher stabilities of compounds that emit green light however, processes associated with CH2Cl2 as the solvent become apparent. LC–MS analysis indeed revealed that the main observed degradation products of

• , possibly competing with the above mentioned reactive oxygen species-induced degradation route may proceed via the excited state of the emitter molecule. This might be due to instability of the excited molecule itself, via interaction of the excited molecule with its local environment or even other excited

• mechanisms. Observations indicating the contribution of the excited states, singlet oxygen and possibly other unidentified pathways to the degradation of Ir(Me-ppy)3 show that the different mechanisms are competing for this emitter. The results from this study furthermore clearly show how even small changes

Palladium-catalyzed synthesis of N-arylated carbazoles using anilines and cyclic diaryliodonium salts

• Stefan Riedmüller and
• Boris J. Nachtsheim

Beilstein J. Org. Chem. 2013, 9, 1202–1209, doi:10.3762/bjoc.9.136

• , or as host or luminescent-materials in electronic devices (OLEDs) (Figure 1) [2][3][4][5][6][7]. Representative examples are the host molecules mCP, CBP and CBZ1-F2, the hole transporter BCz2 [8] or the recently described thermally activated delayed fluorescence (TADF) emitter 4CzIPN [9]. Therefore

Halide exchanged Hoveyda-type complexes in olefin metathesis

• Julia Wappel,
• César A. Urbina-Blanco,
• Mudassar Abbas,
• Jörg H. Albering,
• Robert Saf,
• Steven P. Nolan and
• Christian Slugovc

Beilstein J. Org. Chem. 2010, 6, 1091–1098, doi:10.3762/bjoc.6.125

• field desorption mass spectrometry (FD-MS) measurements. FD-MS was found to be a suitable technique for the characterisation of this type of complex. Selecting appropriate acquisition parameters – the emitter current was slowly increased until desorption/ionisation started, in this way only molecular

Design and synthesis of a cyclitol-derived scaffold with axial pyridyl appendages and its encapsulation of the silver(I) cation

• Pierre-Marc Léo,
• Christophe Morin and
• Christian Philouze

Beilstein J. Org. Chem. 2010, 6, 1022–1024, doi:10.3762/bjoc.6.115

• ; Introduction Despite its recognized potential for nuclear medicine applications [1], the β− emitter 111Ag (t1/2 = 7.47 d), which can be produced carrier-free and with high specific activity [2][3], has not yet found widespread uses [4][5]. This is due in part to the lack of suitable Ag complexing agents and in