Synthesis and Photophysical Properties of Donor- and Acceptor-Substituted 1,7-Bis(arylalkynyl)perylene-3,4:9,10-bis(dicarboximide)s

Extended π-Conjugation and Structural Planarity Effects of Symmetrical D-π-A-π-D Naphthalene and Perylene Diimide Semiconductors on n-type Electrical Properties

A series of donor-π-acceptor-π-donor (D-π-A-π-D) compounds based on naphthalendiimide (NDI) and perylenediimide (PDI) central cores combined with triphenylamine and phenylcarbazole donor groups have been synthesized, characterized and tested in top-contact/bottom gate organic field-effect transistors (OFETs). The results showed high electron mobilities, up to 0.3 cm2  V-1  s-1 , in the case of NDI derivatives and moderate values of around 10-3  cm2  V-1  s-1 for PDI-based semiconductors. Quantum chemical calculations were performed in order to support the experimental data. The results suggest that adequate molecular characteristics and larger crystalline domains in NDI vs. PDI semiconducting films may be the reasons behind the enhanced electrical properties of NDI derivatives. Furthermore, when the lateral donor substituents are triphenylamine groups, the mobilities were slightly higher in comparison to phenylcarbazole donor groups due to an improved electron-donating character. Other characterization techniques, such as AFM, X-ray diffraction or spectroelectrochemistry, among others, have been performed to analyze supramolecular order, charge carriers' nature and stability, parameters closely related to charge transport characteristics.

Rigid Bay-Conjugated Perylene Bisimide Rotors: Solvent-Induced Excited-State Symmetry Breaking and Resonance-Enhanced Two-Photon Absorption

Intramolecular charge transfer and excited-state symmetry breaking have a significant effect on the nonlinear optical properties of multipolar chromophores. Rigid and nonplanar perylene bisimide derivatives (PBIs) functionalized at bay positions were comparatively and comprehensively investigated. In apolar solvents, two quadrupolar molecular rotors showed an obvious decrease of the A_0-0/A_0-1 ratios, suggesting strong exciton coupling with the adjacent PBI units initiated by the π-π stacking. The vanishment of the preferable dimer emission in polar solvents supported the plausible phenomena of excited-state symmetry breaking, thanks to the facile rotation around the rigid linkers. Comparative femtosecond transition absorption studies confirmed their notable differences in relaxation dynamics and the generation of radical anions (PBI^•-) and cations (PBI^•+). The maxima two-photon absorption (2PA) wavelengths obtained for the molecular rotors were slightly red-shifted to 670 nm with intrinsic resonance-enhanced characteristics, reflecting the synergistic effect of functional positions and molecular architectures. Meanwhile, the obvious increase of significant 2PA cross-section values in polar solvents illustrated the stabilization of the symmetry-broken dipolar states. Further femtosecond Z-scan also manifested the contribution of excited-state dynamics on the nonlinear optical properties of multipolar chromophores.

Heavy-Atom-Free Bay-Substituted Perylene Diimide Donor-Acceptor Photosensitizers

Perylene diimide (PDI) dyes are extensively investigated because of their favorable photophysical characteristics for a wide range of organic material applications. Fine-tuning of the optoelectronic properties is readily achieved by functionalization of the electron-deficient PDI scaffold. Here, we present four new donor-acceptor type dyads, wherein the electron donor units - benzo[1,2-b : 4,5-b']dithiophene, 9,9-dimethyl-9,10-dihydroacridine, dithieno[3,2-b : 2',3'-d]pyrrole, and triphenylamine-are attached to the bay-positions of the PDI acceptor. Intersystem crossing occurs for these systems upon photoexcitation, without the aid of heavy atoms, resulting in singlet oxygen quantum yields up to 80 % in toluene solution. Furthermore, this feature is retained when the system is directly irradiated with energy corresponding to the intramolecular charge-transfer absorption band (at 639 nm). Geometrical optimization and (time-dependent) density functional theory calculations afford more insights into the requirements for intersystem crossing such as spin-orbit coupling, dihedral angles, the involvement of charge-transfer states, and energy level alignment.

Near-infrared dyes for two-photon absorption in the short-wavelength infrared: strategies towards optical power limiting

The recent advances in the field of two-photon absorbing chromophores in the short-wavelength infrared spectral range (SWIR 1100–2500 nm) are summarized, highlighting the development of optical power limiting devices in this spectral range.

Nitro-Perylenediimide: An Emerging Building Block for the Synthesis of Functional Organic Materials

Perylenediimide (PDI) is one of the most important classes of dyes and is intensively explored in the field of functional organic materials. The functionalization of this electron-deficient aromatic core is well-known to tune the outstanding optoelectronic properties of PDI derivatives. In this respect, the functionalization has been mostly addressed in bay-positions to halogenated derivatives through nucleophilic substitutions or metal-catalyzed coupling reactions. Being aware of the synthetic difficulties of obtaining the key intermediate 1-bromoPDI, we will present as an alternative in this review the potential of 1-nitroPDI: a powerful building block to access a large variety of PDI-based materials.

Borylated perylenediimide: self-assembly, photophysics and sensing application

A red emissive perylenediimide-triarylboron conjugate (PDI-TAB) with interesting 1D self-assembled nanowires, concentration dependent emission colors and potential fluoride ion sensing is reported.

Perylenetetracarboxy-3,4:9,10-diimide derivatives with large two-photon absorption activity

Perylenetetracarboxy-3,4:9,10-diimides with large TPA cross-sections.

Synthesis and Self-Assembly of Bay-Substituted Perylene Diimide Gemini-Type Surfactants as Off-On Fluorescent Probes for Lipid Bilayers

Interest in bay-substituted perylene-3,4:9,10-tetracarboxylic diimides (PDIs) for solution-based applications is growing due to their improved solubility and altered optical and electronic properties compared to unsubstituted PDIs. Synthetic routes to 1,12-bay-substituted PDIs have been very demanding due to issues with steric hindrance and poor regioselectivity. Here we report a simple one-step regioselective and high yielding synthesis of a 1,12-dihydroxylated PDI derivative that can subsequently be alkylated in a straightforward fashion to produce nonplanar 1,12-dialkoxy PDIs. These PDIs show a large Stokes shift, which is specifically useful for bioimaging applications. A particular cationic PDI gemini-type surfactant has been developed that forms nonfluorescent self-assembled particles in water ("off state"), which exerts a high fluorescence upon incorporation into lipophilic bilayers ("on state"). Therefore, this probe is appealing as a highly sensitive fluorescent labelling marker with a low background signal for imaging artificial and cellular membranes.

Perylene diimide-based organic π-motif for differentiating CN− and F− ions by electron-transfer and desilylation mechanisms: applications to complex logic circuits

PDI-SiHQ undergoes electron-transfer and desilylation reactions with CN⁻ and F⁻ ions to differentiate basic anions.

Vapor-phase polymerization of poly(3, 4-ethylenedioxythiophene) nanofibers on carbon cloth as electrodes for flexible supercapacitors

In this study, an evaporative vapor-phase polymerization approach was employed to fabricate vertically aligned poly(3, 4-ethylenedioxythiophene) (PEDOT) nanofibers on the surface of carbon cloth (CC). Optimized reaction conditions can obtain well distributed and uniform layers of high-aspect-ratio PEDOT nanofibers on CC. The hierarchical PEDOT/CC structure as a freestanding electrode exhibits good electrochemical properties. As a flexible symmetric supercapacitor, the PEDOT/CC hybrid electrode displays a specific areal capacitance of 201.4 mF cm(-2) at 1 mA cm(-2), good flexibility with a higher value (204.6 mF cm(-2)) in the bending state, and a good cycling stability of 92.4% after 1000 cycles. Moreover, the device shows a maximum energy density of 4.0 Wh kg(-1) (with a power density of 3.2 kW kg(-1)) and a maximum power density of 4.2 kW kg(-1) (with an energy density of 3.1 Wh kg(-1)). The results demonstrate that PEDOT may be a promising material for storage devices through a simple and efficient vapor-phase polymerization process with precisely controlled reaction conditions.

Base-driven keto–enol anion tautomerism of a perylene diimide derivative in DMF solution

A perylene diimide derivative (d-THBPDI) containing twisted heptatomic biphenyl substituents in the bay positions exhibited base (hydrazine, 1,2-ethylenediamine, triethylamine and K₂CO₃)-driven keto–enol anion tautomerism in DMF solution.

One-Pot Synthesis of Brightly Fluorescent Mes2B-Functionalized Indolizine Derivatives via Cycloaddition Reactions

Four new BMes2-functionalized indolizine derivatives (Mes = mesityl) have been prepared via the cycloaddition reaction between pyrido[2,1-a]isoindole (A) or pyrrolo[1,2-a]pyridine (B) and BMes2-containing alkynes. All four compounds are brightly blue or blue-green fluorescent with λ(em) = 428-495 nm and Φ = 0.27-0.68, depending on the substitution position of the BMes2 group. Experimental and TD-DFT computational data indicated that the primary electronic transitions responsible for the fluorescence of 1-4 are from HOMO to LUMO (π → π*) rather than charge transfer from N → B, which is in agreement with previous findings suggesting that the lone-pair on N is delocalized throughout the N-heterocycles.

Halochromic and hydrochromic squaric acid functionalized perylene bisimide

A squaric acid functionalized perylene bisimide senses solvent polarity, pH and humidity through the intramolecular charge transfer initiated by protonation/deprotonation.

Colorimetric and fluorimetric detection of fluoride and cyanide ions using tri and tetra coordinated boron containing chromophores

Two organoboron based fluorophores pyrazabole 3 and BODIPY 4 have been designed and synthesized by the Pd-catalyzed Sonogashira cross-coupling reaction and successfully employed for fluoride and cyanide ion sensing.

UV-vis and EPR spectroelectrochemical investigations of triarylamine functionalized arylene bisimides

The ambipolar behavior of groups of N-substituted and core-functionalized triarylamine arylene bisimides were investigated by electrochemical and spectroelectrochemical (UV-vis and EPR spectroelectrochemistry) techniques.

Dual sensing of fluoride ions by the o-carborane-triarylborane dyad

The o-carborane-triarylborane dyad shows high fluoride ion affinity through the trigonal-planar boron center while degradation to nido-carborane leads to a turn-on fluorescence response toward fluoride.

Vibrational Dynamics of a Perylene-Perylenediimide Donor-Acceptor Dyad Probed with Femtosecond Stimulated Raman Spectroscopy

The ultrafast vibrational dynamics of the photoinduced charge-transfer reaction between perylene (Per) and perylene-3,4:9,10-bis(dicarboximide) (PDI) were investigated using femtosecond stimulated Raman spectroscopy (FSRS). Specifically probing the structural dynamics of PDI following its selective photoexcitation in a covalently linked dyad reveals vibrational modes uniquely characteristic to the PDI lowest excited singlet state and radical anion between 1000 and 1700 cm(-1). A comparison of these vibrations to those of the ground state reveals the appearance of new (1*)PDI and PDI(-•) stretching modes in the dyad at 1593 and 1588 cm(-1), respectively. DFT calculations reveal that these vibrations are parallel to the long axis of PDI and thus then may be integral to the charge separation reaction. The ability to differentiate excited state from radical anion vibrational modes allows the evaluation of the influence of specific modes on the charge transfer dynamics in donor-bridge-acceptor systems based on PDI molecular constructs.

2,6-Diacylnaphthalene-1,8:4,5-bis(dicarboximides): synthesis, reduction potentials, and core extension

2,6-Diacyl derivatives of naphthalene-1,8:4,5-bis(dicarboximide)s have been synthesized via Stille coupling reactions of the corresponding 2,6-distannyl derivative with acyl halides. Reaction of these diketones with hydrazine gave phthalazino[6,7,8,1-lmna]pyridazino[5,4,3-gh][3,8]phenanthroline-5,11(4H,10H)-dione fused-ring derivatives. The products were characterized by UV-vis absorption spectroscopy and electrochemistry, modeled using density functional theory calculations, and, in some cases, studied and compared using single-crystal X-ray diffraction.