Isolation of Tetracyano‐Naphthalenediimide and Its Stable Planar Radical Anion

Abstract

Reported herein is the first isolation of tetracyanonaphthalenediimide [NDI(CN) 4 ]a nd its radical anion, and structural elucidation through spectroscopic and X-rayd iffraction studies.T he radical anion shows remarkable stability and was purified by chromatography,w hich is unique for planar radical anions.T he stability results from multiple hydrogen bonds to the counter ion and through an array of intramolecular noncovalent interactions.T he radical anion revealed one of the strongest NDI p-p interactions (3.268 ). Electrochemical studies of [NDI(CN) 4 ]c onfirm its extraordinarily low-lying LUMO (À5.0 eV), rendering it one of the strongest electron-deficient planar p systems to be isolated. The manifold potential, whichremained unknown to date,can now be explored for these open-and closed-shell planar p systems.

Gas-Induced Ion-Free Stable Radical Anion Formation of Organic Semiconducting Solids as Highly Gas-Selective Probes

“…To develop the conditions for gas-induced solid-SRAF of organic materials and demonstrate gas-selective OFET gas sensors through the SRAF mechanism, we chose an n-type semiconducting naphthalene diimide (NDI) core with π-electron-deficient characteristics. − NDI-based small molecular derivatives exhibit good ability to form complex with other molecules − and form radical anions. ,− ,− ,, They also have high electron mobility, good air stability of charge-transporting properties, and high thermal stability. ,,,− Figure shows the chemical structures of NDI–EWG derivatives investigated in this work. As illustrated in Scheme , the π-electron deficiency of an n-type semiconductor NDI core can be enhanced by introducing electron-withdrawing groups (EWGs); then, NDI–EWGs can form an electron-transfer (ET)-induced stable radical anion with the adsorption of Lewis base gases (i.e., gas-on solid-SRAF of NDI/gas complex).…”

“…Despite such appealing merits, gas-induced solid-SRAF of organic semiconducting materials with high gas selectivities has not yet been reported. An effective approach to induce solid-SRAF is to use ionic organic materials with cationic (and zwitterionic) substituents in π-electron-deficient aromatic cores or their counter cations (e.g., phosphonium, pyridinium, and imidazolium), which have strong electron-withdrawing strength. − Although ionic organic materials consisting of n-type semiconducting cores exhibit a strong tendency to stabilize radical anions, the semiconducting characteristics might disappear owing to ionic conductivity (i.e., not suitable for sensitive transistor-based sensors). Consequently, organic semiconducting solids exhibiting ion-free, gas-induced solid-SRAF are highly in demand and very advantageous for various electronic and sensing applications.…”

Supramolecular Nanowires from an Acceptor–Donor–Acceptor Conjugated Chromophore

“…Both OT-1 andO T-2s howed double reversibler eductionw aves in the tested electrochemical window,r epresenting the first reduction of the NMI unit to NMI radicala nion followed by formation of diradical anions localised on each acceptor groups. [16] The first reduction potential shifted to lower values on going from OT-1 (E red1 = À1.10) to OT-2 (E red1 = À0.96), the and the first oxidation potentials were 1.43 and 1.67 eV,r espectively.T he HOMO and LUMO energy levels were calculated to be À5.73 and À3.20 eV for OT-1 and À5.97 and À3.34 eV for OT-2 from the onset of the first oxidation and reductionpotentials, respectively.T he electrochemical band gaps were calculated to be 2.53 and 2.63 eV for OT-1 and OT-2, respectively ( Table 1). The slightly smaller band gap of OT-1 com- Figure 2.…”

The aging effect on the enhancement of thermal stability, mechanical stiffness and fluorescence properties of histidine-appended naphthalenediimide based two-component hydrogels

“…For the last two decades, many attempts have been made to design and construct various gelator molecule with structural diversity through by the covalent attachment with naphthyl 29,30 , pyrene 31,32 , carbazole 33 , cholic acid 34,35 , sugar [36][37][38] and other groups to the lead gelator molecule. Recently, naphthalenediimedes (NDI) based functional materials have become very attractive not only due to their easy synthesis, solubility, redox active nature, chemically robust, molecular planarity, π-acidity and ntype semiconducting nature but also due to the potential application in photovoltaic device 39,40 , field effect transistor 41,42 , solar cell 43,44 , sensing [45][46][47][48] and others [49][50][51][52] . However, low quantum yield restricts their application in the monomeric state of the imide substituted NDI.…”