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A sustainable synthetic method for the synthesis of diporphyrins under ball-milling conditions is reported. The meso-meso linked diporphyrins are efficiently accessed by direct oxidative homo-coupling of porphyrins with Pd(TFA)2 as the catalyst and Cu(OTf)2 as the oxidant.

1,1-Diaryl moieties are core structures in a wide range of bioactive and pharmaceutical compounds. Transition-metal catalysis is a convenient approach to accessing these invaluable compounds affording high yields and enantioselectivities. This review summarizes 1,1-diarylalkanes synthesis through transition metal catalysis. Particular focus is given to recent developments, such as reductive cross-electrophile couplings, benzylic C–H bond arylation, transformations involving metal migration, asymmetric hydrogenation of 1,1-diarylalkenes and three-component coupling reactions.

An approach for the construction of furo[3,2-b]quinolines and furo[2,3-b:4,5-b′]diquinolines is developed through a metal-free [4 + 2] cycloaddition of easily available in situ generated aza-o-quinone methides and furans. The reaction tolerates a wide range of aza-o-quinone methides and substituted furans to afford the corresponding dihydro- or tetrahydrofuroquinolines in good to excellent yields. Mechanistic studies reveal that the reaction involves a concerted [4 + 2] cycloaddition pathway and shows a high regioselectivity of cycloaddition for a furan ring. The present method features mild reaction conditions, dearomatization of furans, high regio- and diastereoselectivity, gram-scalable preparations, and diversity of furoquinolines.

Copper/oxalic diamide-promoted dimerization of tetrachlorinated perylene bisimide to construct highly-fused diperylene bisimides through Ullmann coupling and zipper-mode double C-H activation has been developed in this study. This one-step reaction combining homocoupling with C-H activation proceeded smoothly under the action of inexpensive metal-ligand system. This protocol is expected to expand the available synthetic tools for condensed ring systems of perylene bisimide(PBIs).

We report a metal-free, heterogeneous, inexpensive, and environmentally friendly graphene oxide-catalyzed aza-semipinacol rearrangement of 2-(3-methyleneindolin-2-yl)phenols to prepare 2-(indol-2-yl)phenols and benzofuro[3,2-b]indolines containing quaternary carbon centers in good to excellent yields under mild conditions. The detailed studies demonstrate that graphene oxide can function as a heterogeneous catalyst and provide hydrogen bonding and ion pair interactions on the surface to promote the rearrangement process. The substituent effect on the C2-position of indoline is two-fold, affording 2-(indol-2-yl)phenols by aza-semipinacol rearrangement and benzofuro[3,2-b]indolines by 5-exo-trig cyclization. The stereochemistry of the C3-quaternary carbon center generated from the C2-quaternary carbon center of indoline is retained during the rearrangement. More importantly, the graphene oxide can be easily recovered by washing and recycled seven times without loss of catalytic activity.

Low-grade chronic adipose tissue inflammation contributes to the onset and development of aging-related insulin resistance and type 2 diabetes. In the current study, α-mangostin, a xanthone isolated from mangosteen (Garcinia mangostana), was identified to ameliorate lipopolysaccharides-induced acute adipose tissue inflammation in mice, by reducing the expression of pro-inflammatory cytokines and chemokines. In a cohort of young (3 months) and old (18–20 months) mice, α-mangostin mitigated aging-associated adiposity, hyperlipidemia, and insulin resistance. Further study showed that α-mangostin alleviated aging-related adipose tissue inflammation by reducing macrophage content and shifting pro-inflammatory macrophage polarization. Moreover, α-mangostin protected the old mice against liver injury through suppressing the secretion of microRNA-155-5p from macrophages. The above results demonstrated that α-mangostin represents a new scaffold to alleviate adipose tissue inflammation, which might be a novel candidate to treat aging-related metabolic disorders.

Cyclic sulfonamides (sultams) play a unique role in drug discovery and synthetic chemistry. A direct synthesis of sultams by an intramolecular C(sp3)–H amidation reaction using an iron complex in s...

Four cocrystals were obtained by using 1,4-diiodotetrafluorobenzene and four nitrogen-containing organic coformers, including pyridine, secondary and tertiary amines. The obtained cocrystals have been fully characterized with various techniques, including, single crystal and powder X-ray crystallography, TGA and DSC. Crystal structural analyses showed that halogen bond (XB) is the main driving force responsible for the cocrystallization and for the adopted architectures in the described systems. In the described cocrystals, the 1,4-diiodoperfluorobenzene has shown to be a versatile molecule for intermolecular noncovalent interactions with coformers. Its iodine atoms can serve not only as halogen bond donor, but also as halogen bond acceptor. In addition, it involves also in many non-covalent interactions, including C H⋯F and hole-π … π bondings to play a role in determining the molecular arrangement and crystal packing, which make it an ideal coformer in crystal engineering for predictable and stable supramolecular architecture for desired physicochemical properties.

A variety of 2-(3-methyleneindolin-2-yl)phenols were prepared in good to excellent yields through a NaH-promoted C–C/C–O bond cleavage of fused indolines under mild and simple conditions. Mechanistic studies showed that NaH serves as a nucleophile, attacking the aldehyde group of indoline, which is followed by tandem C–C/C–O bond cleavage to afford the desired products. A representative 2-(3-methyleneindolin-2-yl)phenol was easily prepared on a gram scale.

A general protocol for the construction of novel densely functionalized γ-lactones was developed in good to excellent yields with high diastereoselectivity from easily available N-vinyl-α,β-unsaturated nitrones and ketenes. The reaction involves copper-catalyzed [5 + 2] cycloaddition, N–O bond cleavage, 6π electron cyclization, and aromatization to afford various γ-(pyridin-2-yl)lactones over four step transformations in a single flask. The present method features mild reaction conditions, high atom economy, high regio- and diastereoselectivity, diversity of γ-lactones, and a new application of the O-transfer reaction.

Nitrite anion encapsulation was realized using molecular cavitands of decamethylcucurbit[5]urils as molecular receptors. Single crystal structural analyses showed that the receptors formed sodium-capped molecular capsules that encapsulate nitrite anions inside the cavity. The inclusion entities were proved to be existing in both solution and the solid state. Moreover, the encapsulated nitrite anions could be released and decomposed in acidic solutions.

An approach for the construction of furo[3,2

Graphitic carbon nitride (CN) has attracted worldwide attention due to its low-cost, environmental friendliness and tunable structures. However, the CN photocatalyst still suffers from low charge separation efficiency issues. It is known that mobility is one of the most important factors dominating the charge separation and transport. This work reports a new strategy to address the low charge separation issue by coupling a high-mobility organic semiconductor and CN. Copper phthalocyanine (CuPc), a classical small molecule organic semiconductor which possesses high mobility, outstanding stability and strong visible-light absorption, was selected to construct CN/CuPc heterojunctions. The CN/CuPc heterojunctions showed a high hydrogen evolution (PHE) rate of 9.0 mmol g(-1) h(-1) and apparent quantum yield (AQY) of 3.99% (420 nm) and 1.31% (600 nm). This work demonstrates the application prospects of high-mobility organic semiconductors in heterojunction photocatalysis. Funding Agencies|National Natural Science Foundation of ChinaNational Natural Science Foundation of China (NSFC) [52003143]; Natural Science Foundation of Shandong ProvinceNatural Science Foundation of Shandong Province [ZR2019BB014]; China Scholarship CouncilChina Scholarship Council [201908370037]; Swedish Research Council (Vetenskapsradet)Swedish Research Council [2018-04670]; Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning (FORMAS)Swedish Research Council Formas [2016-00559]; Swedish Foundation for International Cooperation in Research and Higher Education (STINT) [CH2016-6722]

A new derivate of tetracene (DTTA) was synthesized and characterized. From the UV spectrum, compound DTTA showed more stability than rubrene towards photo–oxidization in solid state. The increased stability of DTTA could be explained by the lower energy level of HOMO. Crystal structure is similar to that of rubrene, and based on the calculated results from the Pw91pw91/6-31 g software, good performance of DTTA is expected.

The fabrication of large-scale unidirectionally aligned organic crystalline ribbons is a great challenge. Here, we developed a limited solvent vapor-assisted crystallization (LSVC) method. By adopting an up-side-down funnel, single crystalline microribbons of C8-BTBT with uniform alignment were easily prepared on different substrates, indicating the feasibility of the LSVC method.

A new compound, 2-(2,2-diphenylethenyl) anthracene (DPEA), was designed and synthesized, which showed a hole carrier mobility of 0.66 cm2 V−1 s−1 and typical aggregated induced emission (AIE) behaviour with a ratio of 15 times, which is among the best performance of recently reported semiconducting AIE materials. This work not only enriches the AIE electronic material systems, but also initiates a new direction for developing high performance integrated optoelectronic organic semiconductors for potential multifunctional applications.

Co-crystal containing 1:1 ratio of 4,4′-sulfonyldianiline (dapsone, a sulfonamide antibiotic) and hexamethylenetetramine (HMTA) has been prepared. Herein, we report the synthesis, characterization of the drug-drug co-crystal and its thermal stability. This co-crystal can be prepared by means of solvent evaporation and solid state synthesis (neat ball milling). Single crystal structural characterization of the co-crystal revealed that the co-crystal structure is secured by hydrogen bonds NH 2 ⋯N and multiple weak interactions, including C H⋯π, C H⋯N and C H⋯O, between the co-formers. Moreover, thermal gravimetric analysis showed that the co-former HMTA demonstrates higher thermal stability after co-crystallized with dapsone. These investigations proved that DAP is an ideal parent drug to prepare drug-drug co-crystal. The case study expands the pharmaceutically acceptable solid forms of DAP.

Cyclic sulfonamides (sultams) play a unique role in drug discovery and synthetic chemistry. A direct synthesis of sultams by an intramolecular C(sp

It is challenging to develop simple and low cost catalytic systems while maintaining high reactivity and selectivity. An iron-catalyzed intramolecular C-H amination of sulfamate esters using simple and cheap ligands is reported with general substrate scope (31 examples, up to 95% yield). The addition of second ligand, bipyridine, is able to accelerate the reaction and increase the yield. The ready availability of these iron catalysts provides a promising approach to selective introduction of nitrogen into hydrocarbon feedstock.

Poor charge injection and transport at the electrode/semiconductor contacts has been so far a severe performance hurdle for bottom-contact bottom-gate (BCBG) organic field-effect transistors (OFETs). Here, we have developed a simple, economic, and effective method to improve the carrier injection efficiency and obtained high-performance devices with low cost and widely used source/drain (S/D) electrodes (Ag/Cu). Through the simple electrode etching process, the work function of the electrodes is more aligned with the semiconductors, which reduces the energy barrier and facilitates the charge injection. Besides, the formation of the thinned electrode edge with desirable micro/nanostructures not only leads to the enlarged contact side area beneficial for the carrier injection but also is in favor of the molecular self-organization for continuous crystal growth at the contact/active channel interface, which is better for the charge injection and transport. These effects give rise to the great reduction of contact resistance and the amazing improvement of the low-cost bottom-contact configuration OFETs performance. Accepted version

Inflammation is the body’s self-protective response to multiple stimulus, from external harmful substances to internal danger signals released after trauma or cell dysfunction. Many diseases are considered to be related to inflammation, such as cancer, metabolic disorders, aging, and neurodegenerative diseases. Current therapeutic approaches include mainly non-steroidal anti-inflammatory drugs and glucocorticoids, which are generally of limited effectiveness and severe side-effects. Thus, it is urgent to develop novel effective anti-inflammatory therapeutic agents. Xanthones, a unique scaffold with a 9H-Xanthen-9-one core structure, widely exist in natural sources. Till now, over 250 xanthones were isolated and identified in plants from the families Gentianaceae and Hypericaceae. Many xanthones have been disclosed with anti-inflammatory properties on different models, either in vitro or in vivo. Herein, we provide a comprehensive and up-to-date review of xanthones with anti-inflammatory properties, and analyzed their drug likeness, which might be potential therapeutic agents to fight against inflammation-related diseases.

Theoretical analysis was carried out to investigate the dissociation of gas hydrate in stiff sediment. First the mathematical model for gas hydrate dissociation was decoupled by asymptotic expansion method considering the order differences of time scales among seepage, dissociation of gas hydrate and heat conduction. The multi-scale perturbation method was used to solve the problem. It is shown that seepage is the fastest process. The heat conduction is the slowest process. With the pressure decreases at the boundary, pressure changes first while no hydrate dissociation and heat conduction occur. Gradually, dissociation causes the decrease of temperature. After a long time, heat can conduct to cause the increase of temperature. Otherwise, the decreased temperature will cause the stop of dissociation if no heat is supplied in time.

Thienyl substituted cyclobutenes with aggregation induced emission behaviour have been synthesized for the first time in good selectivity, opening the possibility of cyclobutenes for application in light emitting diodes.

A new thienyl peripherally substituted rubrene analogue was synthesized. Different from rubrene quenching of fluorescence after aggregation, this compound emits constantly yellow-green light both in solution and in the aggregation state. Meanwhile, this rubrene analogue exhibits better film forming ability with the hole charge carrier mobility up to 0.01 cm2 V−1 s−1.

A novel and convenient cascade trifluoroethylation/cyclization of organic isoselenocyanates by phenyl(2,2,2-trifluoroethyl)iodonium triflate is reported. A series of 2-isoselenocyanobiaryls and aryl alkyl isoselenocyanates reacted with phenyl(2,2,2-trifluoroethyl)iodonium triflate in CH2Cl2 at 40 °C under metal- and additive-free conditions for 3 h to provide the corresponding trifluoroethylselenolated phenanthridines and 3,4-dihydroisoquinoline derivatives in good to excellent yields. The reaction represents the first general approach to access trifluoroethylselenolated phenanthridines and 3,4-dihydroisoquinolines from organic isoselenocyanates.

Interfacial compatibility and particles dispersion are two vital influences for improving mechanical properties of silicone rubber (SR) nanocomposites. To achieve a high level of compatibility with SR-matrix, a series of dispersible nanosilica (denoted as DNS) surface modified with hexamethyldisilazane (HMDS) as well as aluminum hydroxide modified with stearic acid (denoted as m-ATH) were synthesized and used as reinforcement fillers of SR-matrix nanocomposites. Results indicate that the compatibility can be obviously improved by modification of fillers. DNS surface-capped with 0.1 mol l−1 HMDS and m-ATH surface-modified with 0.1 wt% stearic acid exhibit excellent reinforcement effect. Compared with unmodified samples, the tear strength and elongation at break have been improved by 68.5% and 171.2%, respectively. Moreover, the as-fabricated DNS/m-ATH nanocomposite exhibits a tracking-erosion resistance of 1 A 4.5–0.83, a volume resistivity of 1.0 × 1015 Ωcm and a dielectric constant of up to 3.51, which are all much higher than the standards of high voltage insulator sheds. This indicates that the as-fabricated SR-matrix nanocomposite could be a qualified candidate material for high voltage insulator sheds.

Ultraviolet-shielding and conductive double functional films were composed of CeO 2 -TiO 2 film and SnO 2 :Sb film deposited on glass substrates using sol-gel process. Ce(NO 3 ) 3 ·6H 2 O and Ti(C 4 H 9 O 4 ), SnCl 4 and SbCl 3 were used as precursors of the two different functional films respectively. The CeO 2 -TiO 2 films were deposited on glass substrates by sol-gel dip coating method, and then the SnO 2 : Sb films with different thickness were deposited on the pre-coated CeO 2 -TiO 2 thin film glass substrates, finally, the substrates coated with double functional films were annealed at different temperatures. The optical and electrical properties of the CeO 2 -TiO 2 films and the double films were measured by UV-Vis spectrometer and four probe resistance measuring instrument. The crystal structures and surface morphology of the films were characterized using XRD and optical microscope, respectively. The obtained results show that the ultraviolet-shielding rate of the glass substrates with CeO 2 -TiO 2 films is not less than 90%, and transmittance in visible lights can reach 65%. With the thickness of the SnO 2 :Sb film increasing, its conductivity became better, and the surface resistance is about 260 Ω/□ when the SnO 2 :Sb films were deposited 11 cycles of the dip on the pre-coated CeO 2 -TiO 2 glass. The ultraviolet-shielding rate of the glass substrates with double functional films is higher than 97%, and the peak transmittance in the visible lights is 72%. Additionally, with increasing the heat treatment time, the Na + of the glass substrates diffuses into the films, resulting in the particle size of SnO 2 crystal smaller.

The first example for thienoacene derivatives with selective growth of different crystal polymorphs is simply achieved by solution-phase self-assembly. Compared with platelet-shaped α-phase crystals, organic field-effect transistors (OFETs) based on microribbon-shaped β-phase crystals show a hole mobility up to 18.9 cm(2) V(-1) s(-1), which is one of the highest values for p-type organic semiconductors measured under ambient conditions.

In this article, we demonstrated a method to synthesize graphene films at low temperature via a mild radical-coupling reaction. During the deposition process, with the effectively breaking of the C-Br bonds of hexabromobenzene (HBB) precursors, the generated HBB radicals couple efficiently to form graphene films at the low temperature of 220-250 °C. In situ low-temperature scanning tunneling microscopy was used to provide atomic scale investigation of the graphene growth mechanism using HBB as precursor. The chemical structure evolution during the graphene growth process was further corroborated by in situ X-ray photoelectron spectroscopy measurements. The charge carrier mobility of the graphene film grown at low temperature is at 1000-4200 cm(2) V(-1) s(-1), as evaluated in a field-effect transistor device configuration on SiO2 substrates, indicating the high quality of the films.

By introducing phenyl groups into the 2- and 6-positions of 11,11,12,12-tetracyano-9,10-anthraquinodimethane, a material (dP-TCAQ) with aggregation-induced emission enhancement (AEE) characteristics was synthesized. The AEE phenomenon was explained by analysis of its solid-state packing mode. To our best knowledge, this is the first report regarding 11,11,12,12-tetracyano-9,10-anthraquinodimethane with AEE behaviour.