Naphthalene Diimides Prepared by a Straightforward Method and Their Characterization for Organic Electronics

Abstract

A new approach for the synthesis of acetylene‐substituted naphthalene diimides in polar solvents with PdCl2, Et3N, and electrolytic copper powder was developed. This simplified approach allows for high‐throughput synthesis, and the reaction products can be readily separated. DFT studies revealed that the electronic structures of these compounds are mainly determined by the central naphthalene diimide unit and the acetylene groups. The obtained thermally stable and soluble compounds undergo reversible reduction with electron affinities of 4.18 to 4.28 eV. They emit green light with photoluminescence quantum yields of ca. 6 % in chloroform and in the range 3–12 % as thin films. The compounds were applied as emitting layers for both nondoped and doped single‐layer organic light‐emitting diodes (OLEDs) fabricated by solution processing. Under an applied external voltage, they exhibit orange or red electroluminescence.

New Acceptor–Donor–Acceptor Systems Based on Bis-(Imino-1,8-Naphthalimide)

“…Moreover, the bisnaphthalimides described so far in their core contained the following derivatives: phenyl, carbazole, triphenylamine, thiophene or bitiophene ( Figure S1 ) [ 51 ]. To bisnaftaloimisdes are also include structures through the imide part [ 52 , 53 , 54 ] as well as through a bridge, e.g., amide [ 55 , 56 ]. Should be noted that the current research focuses on the synthesis and study of derivatives substituted in the 4-C position of the naphthalimide ring [ 51 ] while there are few reports on derivatives substituted in the 3-C position of the naphthalimide [ 45 ], as was mentioned above.…”

Synthesis and Surface Behaviour of NDI Chromophores Mounted on a Tripodal Scaffold: Towards Self‐Decoupled Chromophores for Single‐Molecule Electroluminescence

“…Amongst others, [2] various derivatives of naphthalene‐1,4,5,8‐tetracarboxdiimides (NDIs) are widely used for organic electronics due to their by core substituents tuneable electronic and optical properties, [3] their chemical and photochemical stability, [3,4] and their favourable electron transport properties [5,6] . Consequently, OLEDs based on these subunits have been recently reported [7,8] . Although Vollmann et al.…”

“…The colours of core‐substituted NDIs originate from a charge transfer band that moves to the red over the full rainbow spectrum with increasing push‐pull character between the core substituent and the NDI core. While photoluminescence properties of NDIs have been extensively studied, [3] their electroluminescence behaviour is barely studied [7,8] . Given their synthetic accessibility, tuneable photophysical properties, reversible electrochemistry, [15,16] ground‐ and excited state stability, and structural integrity, NDIs are particular appealing chromophores for the development of model compounds to investigate single molecule electroluminescence.…”

Water soluble organic electrochromic materials

“…Given the high toxicity of viologens, it is preferrable to use a safer compound in water processable ECDs, such as naphthalene diimide (NDI). Naphthalene diimides, along with the related compounds perylene bisimide (PBIs), are commonly used as n-type materials in a wide variety of organic electronic devices including solar cells, 69,70 eld effect transistors, 71,72 light emitting diodes, 73,74 and ECDs. 75,76 They possess high electron affinity and extensive p-systems that provide stability for radical species and as such can be readily reduced.…”