Difuran Derivatives Research Articles

Optoelectronic properties of naphtho[2, 1-b:6, 5-b′]difuran derivatives for photovoltaic application: a computational study

Some important optoelectronic properties of naphtho[2,1-b:6,5-b']difuran (DPNDF) and its two derivatives have been limelighted by applying the density functional theory (DFT). Due to their low cost, high stability and earth abundance, the DPNDF and its derivatives are considered as potential organic semiconductor materials for their optoelectronics applications. Highly proficient derivatives are obtained systematically by attaching -CN (cyanide) to DPNDF at various sites. Our calculations indicate that DPNDF has a wide and direct band gap with an energy gap of 3.157eV. Whereas the band gaps of its derivatives are found to be decreased by 88meV for derivative "a" and 300meV for derivative "b" as a consequence of p orbitals present in C and N atoms in derivative structures. The narrowing of the energy gap and density of states for the derivatives of DPNDF in the present investigation suggest that energy gap can be engineered for desirable optoelectronic applications via derivatives designing. Furthermore, their obtained results for optical parameters such as the dielectric and conductivity functions, reflectivity, refractive index, and the extinction coefficients endorses their aptness for optoelectronic applications. Graphical Abstract Real part of dielectric function for derivative "b".

Effect of donor strength of extended alkyl auxiliary groups on optoelectronic and charge transport properties of novel naphtha[2,1-b:6,5-b']difuran derivatives: simple yet effective strategy.

The present study spotlights the designing of new derivatives of 2,7-bis (4-octylphenyl) naphtho [2,1-b:6,5-b'] difuran (C8-DPNDF) by substituting the alkyl groups (methyl, ethyl, propyl, butyl, pentyl, hexyl, and heptyl groups) at para position. Density functional theory (DFT) and time-dependent density functional theory (TD-DFT) methods are employed to optimize the molecular structures in ground and first excited states, respectively. Several electro-optical properties including hole/electron reorganization energies (λh/λe), electron affinities (EAs), ionization potentials (IPs), molecular electrostatic potentials (MEP), and frontier molecular orbitals (FMOs) have been evaluated. Furthermore their transfer integrals and intrinsic mobilities values have also been calculated. From this study, it is found that hole mobility of octyl containing derivative is raised to 4.69 cm(2) V(-1) s(-1). Moreover with attaching octyl group, hole transfer integral values have also been enhanced in newly designed derivatives. The balanced hole and electron reorganization energies, and improved transfer integrals lead to enhanced mobility in derivatives with octyl group, highlighting them as an efficient hole transfer material. Unlike the other electro-optical properties, the intrinsic hole mobility has increased because of transfer integral values of octyl containing derivative C8-DPNDF due to the dense and close crystal packing of C8-DPNDF. However, photostability of furan-based materials has not changed by increasing length of extended alkyl chain. Thus our present investigation highlights the importance of alkyl auxiliary groups that are often neglected/replaced with simple methyl group to save computation costs. Graphical Abstract The hole and electron reorganization energies of naphtho[2,1-b:6,5-b']difuran derivatives.

Effects of carbon chain on hole-transport properties in naphtho[2,1-b:6,5-b′]difuran derivatives: Remarkable anisotropic mobilities

Theoretical investigations of hole-transport properties in two naphtho[2,1-b:6,5-b′]difuran derivatives as novel p-type organic semiconductor based on the Marcus–Hush theory combining quantum mechanics are carried out. This work focuses on the effects of carbon chain on molecular orbitals, partial charge difference, ionization potential, internal energy relaxation, and hole-transport behaviors. Through computational modeling, we are shedding light on the favorable function of C8-DPNDF single crystal as p-type organic material. With the introduction of octyl group, C8-DPNDF single crystal possesses high hole-transfer mobilites (1.589cm2V−1s−1) and remarkable anisotropic behavior. The simulated anisotropic mobility curve of C8-DPNDF demonstrates the maximum value of the mobility appears when the measuring conducting channel is along the b-axis of the single crystal. The adiabatic ionization potential (AIP) and vertical ionization potential (VIP) of C8-DPNDF are about 6.312 and 6.399eV, that is, slightly smaller than those of DPNDF. The relatively small IP values can ensure effective hole injection from the source electrode. The data obtained from the present work can be used to prove that C8-DPNDF molecule has the potential to develop into high-efficient p-type organic semiconductor materials, whose hole-transport mobility can be further improved when the measuring transistor channel is controlled carefully.

Effects of Electron Withdrawing Groups on Transfer Integrals, Mobility, Electronic and Photo-Physical Properties of Naphtho[2,1-b:6,5-b′]Difuran Derivatives: A Theoretical Study

Effects of Electron Withdrawing Groups on Transfer Integrals, Mobility, Electronic and Photo-Physical Properties of Naphtho[2,1-b:6,5-b′]Difuran Derivatives: A Theoretical Study

Pyreno[4,5-b]furan and Pyreno[4,5-b:9,10-b′]difuran Derivatives as New Blue Fluorophores: Synthesis, Structure, and Electronic Properties

New pyreno[4,5-b]furan and pyreno[4,5-b:9,10-b′]difuran derivatives displaying intense blue fluorescence in CH2Cl2 were efficiently synthesized through the reactions of pyrene-4,5-dione and 2,7-di-tert-butylpyrene-4,5,9,10-tetraone with benzylphosphoranes as a key step. X-ray crystallographic analysis reveals that both pyrenofurans have a planar structure, and their electrochemical properties obviously indicate high HOMO energy levels as predicted by density functional theory (DFT) calculations.

Synthesis of a new class of highly fluorescent aryl-vinyl benzo[1,2-b:4,5-b′]difuran derivatives

The synthesis of 2-(2-arylvinyl)- and 2,6-di(2-arylvinyl)dibenzo[1,2-b:4,5-b′]furan derivatives for application in optoelectronics is described. Wittig reaction of the triphenylphosphonium bromides derived from diethyl 2,6-dimethylbenzofuro[5,6-b]furan-3,7-dicarboxylate with aryl aldehydes gave the products in 70–99% yield. The corresponding products derived from furfural and cinnamic aldehyde were also obtained. The prepared products reveal UV–Vis fluorescence with quantum yields, varying from 1% to 100%, and may be used as organic small molecule materials for organic light-emitting devices (OLED).

Naphtho[2,1-b:6,5-b′]difuran: A Versatile Motif Available for Solution-Processed Single-Crystal Organic Field-Effect Transistors with High Hole Mobility

We here report naphtho[2,1-b:6,5-b']difuran derivatives as new p-type semiconductors that achieve hole mobilities of up to 3.6 cm(2) V(-1) s(-1) along with high I(on)/I(off) ratios in solution-processed single-crystal organic field-effect transistors. These features originate from the dense crystal packing and the resulting large intermolecular π-orbital overlap as well as from the small reorganization energy, all of which originate from the small radius of an oxygen atom.

Synthesis of benzo[1,2-b:4,5-b′]difuran derivatives utilizing concomitant photocyclization and photo-Fries rearrangement reactions

A synthetic route for 2,6-dialkyl-3,7-diphenylbenzo[1,2-b:4,5-b′]difurans 1a–c (a: alkyl = n-C7H15; b: alkyl = CH3; c: alkyl = (CH2)7Br) from p-dimethoxybenzene utilizing photocyclization and photo-Fries rearrangement reactions is described. Dimethoxybenzene was reacted with benzoyl chloride to obtain 3-benzoyl-4-hydroxyphenyl benzoate 5, and the reaction of 5 with alkyl halides gave 4-alkoxy-3-benzoylphenyl benzoates 6a–c. Photoirradiation of 6a–c followed by dehydration afforded 2-alkyl-6-benzoyl-5-hydroxy-3-phenylbenzofurans 7a–c via concomitant photocyclization and photo-Fries rearrangement. Etherification of 7a–c with alkyl halides gave 5-alkoxy-2-alkyl-6-benzoyl-3-phenylbenzofurans 11a–c, and photocyclization/dehydration reaction of 11a–c provided 2,6-dialkyl-3,7-diphenylbenzo[1,2-b:4,5-b′]difuran compounds 1a–c. A cyclophane containing both benzo[1,2-b:4,5-b′]difuran and naphthalene rings was also prepared by the coupling of 1c with 2,7-dihydroxynaphthalene.

The synthesis of quinodimethanes in the benzodifuranone and benzodipyrrolidone series

The condensation of hydroquinone and 2,5-substituted hydroquinones with mandelic acids, or of 1,4-benzoquinone and 2,5-substituted 1,4-benzoquinones with mandelic acids or arylacetic acids gives 3,7-diaryl- 2,6-dioxo- 2,6-dihydrobenzo[ 1,2-b: 4,5-b′]difuran derivatives. Analogous benzodipyrrolidones have been obtained from 1,4-phenylenediamine and N,N′-dimethyl- 1,4-phenylenediamine. Both series are novel chromogens and have application as dyestuffs. The red compound obtained from 1,4-benzoquinone and cyanoacetic acid and reported to be a lin-pentacenetriquinone has been shown to be 3,7-bis( 4-hydroxyphenyl) 2,6-dioxo- 2,6-dihydrobenzo[ 1,2-b: 4,5-b′]difuran.

The chemistry of acetals

The reaction of butyndial tetramethylacetal with acetoacetic ester in the presence of boron trifluoride etherate is investigated, and is shown to give 5, 5′-dimethyl-4, 4′-dicarbethoxy-2, 2′-difuryl. The reaction is extended to synthesize some difuran derivatives.