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Seeking high-performance photoresists is an important item for semiconductor industry due to the continuous miniaturization and intelligentization of integrated circuits. Polymer resin containing carbonate group has many desirable properties, such as high transmittance, acid sensitivity and chemical formulation, thus serving as promising photoresist material. In this work, a series of aqueous developable CO 2 -sourced polycarbonates (CO 2 -PCs) were produced via alternating copolymerization of CO 2 and epoxides bearing acid-cleavable cyclic acetal groups in the presence of tetranuclear organoborane catalyst. The produced CO 2 -PCs were investigated as chemical amplification resists in deep ultraviolet (DUV) lithography. Under the catalysis of photogenerated acid, the acetal (ketal) groups in CO 2 -PC were hydrolysed into two equivalents of hydroxyl groups, which change the exposed area from hydrophobicity to hydrophilicity, thus enabling the exposed area to be developed with water. Through normalized remaining thickness analysis, the optimal CO 2 -derived resist achieved a remarkable sensitivity of 1.9 mJ/cm 2 , a contrast of 7.9, a favorable resolution (750 nm, half pitch), and a good etch resistance (38 % higher than poly(tert-butyl acrylate)). Such performances outperform commercial KrF and ArF chemical amplification resists (i.e., polyhydroxystyrene-derived and polymethacrylate-based resists), which endows broad application prospects in the field of DUV (KrF and ArF) and extreme ultraviolet (EUV) lithography for nanomanufacturing., (© 2024 Wiley-VCH GmbH.)

Alkyl borane compounds-mediated polymerizations have expanded to Lewis pair polymerization, free radical polymerization, ionic ring-opening polymerization, and polyhomologation. The bifunctional organoborane catalysts that contain the Lewis acid and ammonium or phosphonium salt in one molecule have demonstrated superior catalytic performance for ring-opening polymerization of epoxides and ring-opening copolymerization of epoxides and CO 2 than their two-component analogues, i.e., the blend of organoborane and ammonium or phosphonium salt. To explore the origin of the differences of the one-component and two-component organoborane catalysts, here we conducted a systematic investigation on the catalytic performances of these two kinds of organoborane catalysts via terpolymerization of epoxide, carbon dioxide and anhydride. The resultant terpolymers produced independently by bifunctional and binary organoborane catalyst exhibited distinct microstructures, where a series of gradient polyester-polycarbonate terpolymers with varying polyester content were afforded using the bifunctional catalyst, while tapering diblock terpolymers were obtained using the binary system. The bifunctional catalyst enhances the competitiveness of CO 2 insertion than anhydride, which leads to the premature incorporation of CO 2 into the polymer chains and ultimately results in the formation of gradient terpolymers. DFT calculations revealed the role of electrostatic interaction and charge distribution caused by intramolecular synergistic effect for bifunctional organoborane catalyst., (© 2024 Wiley-VCH GmbH.)

This work reported that a silicon-centered alkyl borane/ammonium salt binary (two-component) catalyst exhibits much higher activity than its bifunctional analogue (one-component) for the ring-opening polymerization of propylene oxide, showing 7.3 times the activity of its bifunctional analogue at a low catalyst loading of 0.01 mol %, and even 15.3 times the activity at an extremely low loading of 0.002 mol %. By using 19 F NMR spectroscopy, control experiments, and theoretical calculation we discovered that the central silicon atom displays appropriate electron density and a larger intramolecular cavity, which is useful to co-activate the monomer and to deliver propagating chains, thus leading to a better intramolecular synergic effect than its bifunctional analogue. A unique two-pathway initiation mode was proposed to explain the unusual high activity of the binary catalytic system. This study breaks the traditional impression of the binary Lewis acid/nucleophilic catalyst with poor activity because of the increase in entropy., (© 2023 Wiley-VCH GmbH.)

Poly(cyclopentene carbonate) (PCPC) produced by copolymerization of CO 2 and cyclopentene oxide (CPO) is a promising but challenging chemical recyclable polymer that has high potential in minimizing plastic pollution and maximizing CO 2 utilization. Currently, problems remain to be solved, include low reactivity of toxic metal catalysts, inevitable byproducts, and especially the ambiguous mechanism understanding. Herein, we present the first metal-free access to PCPC by using a series of modular dinuclear organoboron catalysts. PCPC was afforded in an unprecedented catalytic efficiency of 1.0 kg of PCPC/g of catalyst; while the depolymerization of PCPC abides by a combination pathway of random chain scission and chain unzipping, returning CPO in near-quantitative yield (>99 %). The preparation and depolymerization of PCPC along with in depth understanding of related mechanisms would be helpful for further development of advanced catalysts and recyclable plastics., (© 2022 Wiley-VCH GmbH.)

Defect states play an important role in the photovoltaic performance of metal halide perovskites. Particularly, the passivation of surface defects has made great contributions to high-performance perovskite photovoltaics. This highlights the importance of understanding the surface defects from a fundamental level by developing more accurate and operando characterization techniques. Herein, a strategy to enable the surface carriers and photocurrent distributions on perovskite films to be visualized in the horizontal direction is put forward. The visual image of photocurrent distribution is realized by combining the static local distribution of carriers provided by scanning near-field optical microscopy with the dynamic transporting of carriers achieved via a scanning photocurrent measurement system. Taking a surface passivated molecule as an example, a comprehensive defect scene including static and dynamic as well as local and entire conditions is obtained using this strategy. The comprehensive analysis of the trap states in perovskite films is pioneered vertically and horizontally, which will powerfully promote the deep understanding of defect mechanisms and carrier behavior for the goal of fabricating high-performance perovskite optoelectronic devices., (© 2022 Wiley-VCH GmbH.)

Construction of well-defined sulfur-rich macromolecules in a facile manner is an interesting but challenging topic. Herein, we disclose how to readily construct well-defined triblock sulfur-rich thermoplastic elastomers via a self-switchable isothiocyanate/episulfide copolymerization and air-assisted oxidative coupling strategy. During self-switchable polymerization, alternating copolymerization of isothiocyanate and episulfide occurs initially due to the lower energy barrier for isothiocyanate insertion with respect to successive episulfide ring-opening. After exhaustion of isothiocyanate, ring-opening polymerization of episulfide begins, providing diblock polymers. Subsequent exposure of the reaction to air leads to a transformation of diblock copolymers into triblock thermoplastic elastomers. This protocol can be extended to diverse isothiocyanates and episulfides, allowing fine-tuning of the performance of the produced sulfur-rich thermoplastic elastomers., (© 2021 Wiley-VCH GmbH.)

White-light-emissive organic micro/nanostructures hold exotic potential applications in full-color displays, on-chip wavelength-division multiplexing, and backlights of portable display devices, but are rarely realized in organic core/shell heterostructures. Herein, through regulating the noncovalent interactions between organic semiconductor molecules, a hierarchical self-assembly approach of horizontal epitaxial-growth is demonstrated for the fine synthesis of organic core/mono-shell microwires with multicolor emission (red-green, red-blue, and green-blue) and especially organic core/double-shell microwires with radial red-green-blue (RGB) emission, whose components are dibenzo[g,p]chrysene (DgpC)-based charge-transfer (CT) complexes. In fact, the desired lattice mismatching (≈2%) and the excellent structure compatibility of these CT complexes facilitate the epitaxial-growth process for the facile synthesis of organic core/shell microwires. With the RGB-emissive substructures, these core/double-shell organic microwires are microscale white-light sources (CIE [0.34, 0.36]). Besides, the white-emissive core/double-shell microwires demonstrate the fascinating full-spectrum light transportation from 400 to 700 nm. This work indeed opens up a novel avenue for the accurate construction of organic core/shell heterostructures, which provides an attractive platform for the organic integrated optoelectronics., (© 2021 Wiley-VCH GmbH.)

Producing polyesters with high molecular weight (M n ) through ring-opening copolymerization (ROCOP) of epoxides with cyclic anhydrides remains a major challenge. Herein, we communicate a metal-free, highly active, and high thermoresistance system for the ROCOP of epoxides with cyclic anhydrides to prepare polyesters (13 examples). The organoboron catalysts can endure a reaction temperature as high as 180 °C for the ROCOP of cyclohexane oxide (CHO) with phthalic anhydride (PA) without the observation of any side reactions. The average M n of the produced poly(CHO-alt-PA) climbed to 94.5 kDa with low polydispersity (Ð=1.19). Furthermore, an unprecedented turnover number of 9900, equivalent to an efficiency of 7.4 kg of polyester/g of catalyst, was achieved at a feed ratio of CHO/PA/catalyst=20000:10000:1 at 150 °C. Kinetic studies, crystal structure analysis, 11 B NMR spectra, and DFT calculations provided mechanistic justification for the effectiveness of the catalyst system., (© 2021 Wiley-VCH GmbH.)

Photocatalytic water splitting coupled with the production of highly value-added organic chemicals is of significant importance, which represents a very promising pathway for transforming green solar energy into chemical energy. Herein, we report a composite photocatalyst CdIn 2 S 4 @MIL-53-SO 3 Ni 1/2 , which is highly efficient on prompting water splitting for the production of H 2 in the reduction half-reaction and selective oxidation of organic molecules for the production of highly value-added organic chemicals in the oxidation half-reaction under visible light irradiation. The superior photocatalytic properties of the composite photocatalyst CdIn 2 S 4 @MIL-53-SO 3 Ni 1/2 should be ascribed to coating suspended ion catalyst (SIC), consisting of redox-active Ni II ions in the anionic pores of coordination network MIL-53-SO 3 - , on the surface of photoactive CdIn 2 S 4 , which endows photogenerated electron-hole pairs separate more efficiently for high rate production of H 2 and selective production of highly value-added organic products, demonstrating great potential for practical applications., (© 2021 Wiley-VCH GmbH.)

A series of highly active organoboron catalysts for the coupling of CO 2 and epoxides with the advantages of scalable preparation, thermostability, and recyclability is reported. The metal-free catalysts show high reactivity towards a wide scope of cyclic carbonates (14 examples) and can withstand a high temperature up to 150 °C. Compared with the current metal-free catalytic systems that use mol % catalyst loading, the catalytic capacity of the catalyst described herein can be enhanced by three orders of magnitude (epoxide/cat.=200 000/1, mole ratio) in the presence of a cocatalyst. This feature greatly narrows the gap between metal-free catalysts and state-of-the-art metallic systems. An intramolecular cooperative mechanism is proposed and certified on the basis of investigations on crystal structures, structure-performance relationships, kinetic studies, and key reaction intermediates., (© 2020 Wiley-VCH GmbH.)

This manuscript describes a kind of bifunctional organocatalyst with unprecedented reactivity for the synthesis of polyethers via ring-opening polymerization (ROP) of epoxides under mild conditions. The bifunctional catalyst incorporates two 9-borabicyclo[3.3.1]nonane centers on the two ends as Lewis acidic sites for epoxide activation and a quaternary ammonium halide in the middle as the initiating site. The catalyst could be easily prepared in two steps from commercially available stocks on up to kilogram scale with ≈100 % yield. The organoboron catalyst mediated ROP of epoxides displays living behavior with low catalyst loading (5 ppm) and enables the synthesis of polyethers with molecular weights of over a million grams per mole (>10 6  g mol -1 ). Based on the investigations on crystal structure of catalyst, MALDI-TOF, and 11 B NMR spectroscopy, an intramolecular ammonium cation assisted S N 2 mechanism is proposed and verified by DFT calculations., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The development of solvent-free, metal-free, recyclable organic catalysts is required for the current chemical fixation of carbon dioxide converted into cyclic carbonates. With the goal of reducing the cost, time, and energy consumption for the coupling reaction of CO 2 and epoxides, a series of highly active heterogeneous catalysts, based on a thiourea and quaternary ammonium salt system, are synthesized by using a thiol-ene click reaction under ultraviolet light. Benefitting from synergistic interactions of the electrophilic center (thiourea) and the nucleophilic site (ammonium bromide), the catalysts exhibit excellent catalytic selectivity (99 %) for the cycloaddition of carbon dioxide with a diverse range of epoxides under mild conditions (1.2 MPa, 100 °C). Moreover, the catalyst can be easily recycled by facile filtration and reused for 5 times without noticeable loss of activity and selectivity. This work provides a potential heterogeneous catalyst for the conversion of carbon dioxide into high value-added chemicals with the combined advantages of low cost, easy recovery, and satisfactory catalytic properties., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Safflower has both medicinal and edible values but research on its nutrient composition is still lacking. This study was established for the quantitative determination of 28 nucleosides, nucleobases, and amino acids based on the ultra-performance liquid chromatography coupled with triple-quadrupole linear ion-trap tandem mass spectrometry. Analysis of 30 batches of safflower from different producing areas indicated that the contents of l-proline, l-asparagine, l(+)-arginine, l-serine, l-histidine, uracil, guanosine, and uridine was high in safflower. Principle component analysis and cluster analysis found that samples from different regions could be distinguished well, and samples from the same area could be clustered into one class, different geographical environments may cause the differences of nucleosides, nucleobases, and amino acids in safflower. The analysis of principal component analysis, cluster analysis, and counter propagation artificial neural network show similar results. Then the content of nucleosides, nucleobases, and essential amino acids were compared, and found that the content in safflower from Gansu was higher than those from other regions, and there was a little difference between the samples from Xinjiang, Sichuan, and Yunnan. This research revealed the composition of nucleosides, nucleobases, and amino acids in safflower, and provided a theoretical basis for utilization of safflower., (© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The use of molecular iodine to tune the electrical conductivity in metal-organic frameworks is an effective but seldom investigated strategy. Herein, the single-crystal-to-single-crystal transformation of [Co 1.5 (bdc) 1.5 (H 2 bpz)]⋅DMF⋅4 H 2 O (1) to [Co 1.5 (bdc) 1.5 (H 2 bpz)]⋅0.5 I 2 ⋅DMF (I 2 @1) (H 2 bdc=1,4-benzenedicarboxylic acid, H 2 bpz=3,3',5,5'-tetramethyl-4,4'-bipyrazole) upon I 2 loading caused a three orders of magnitude enhancement in electrical conductivity of the framework. Single-crystal X-ray diffraction revealed that I 2 exists as a single molecule embedded in the channels of framework, and the C-H⋅⋅⋅I hydrogen bonds between I 2 molecules and phenyl units on the porous surface of the framework were suggested to participate in n→σ* host-guest charge transfer, leading to increased electrical conductivity in I 2 @1. Furthermore, 1 displayed moderate adsorption selectivity for CO 2 over CH 4 and N 2 ., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Three metal-organic frameworks (MOFs), [Cd(Hpzbpdc)(H 2 O)]⋅H 2 O (1), [Mn 2 (Hpzbpdc) 2 (dmf) 2 ] (2), and [H 2 N(CH 3 ) 2 ] 0.5 [Eu(Hpzbpdc) 1.5 (HCOO) 0.5 (dmf) 0.5 ]⋅DMF⋅0.5 H 2 O (3) (H 3 pzbpdc=4'-(2 H-pyrazol-3-yl)biphenyl-3,5-dicarboxylic acid), have been solvothermally synthesized from one pyrazoyl-carboxyl bifunctional ligand and characterized by single-crystal structures. The H 3 pzbpdc ligand in 1-3 displays various coordination modes through the pyrazoyl and carboxyl groups. Both 1 and 3 contain dinuclear cluster building units and reveal a four-connected gismondine (gis) zeolite 3D framework and a 2D grid layer structure, respectively. Compound 1 shows blue luminescence, compound 3 reveals red luminescence that arises from efficient energy transfer from the organic ligand to the europium(III) ion, and compound 2 reveals an uncommon (3,8)-connected tfz-d; UO 3 net with a rare Mn 4 (COO) 6 cluster and shows antiferromagnetic interactions between the manganese(II) ions., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Luminescent metal-organic frameworks (LMOFs) containing fluorescent probes for the detection of pollutants such as organic solvents and heavy metals are becoming increasingly important, with lanthanide-MOF (Ln-MOF) materials receiving greater attention owing to the possibility of achieving fine-tuned luminescent properties. Herein, two unusual isostructural nanocage-based three-dimensional Ln-MOFs, 1-Ln (Ln=Tb, Eu), are constructed, using a new diisophthalate ligand with active Lewis basic triazole sites. Selective gas adsorption, especially the removal of CO 2 from CH 4 , a primary component of natural gas and biogas, is desirable in terms of both economic and environmental considerations. 1-Eu is found to exhibit highly efficient luminescent sensing for Fe 3+ cations and Cr 2 O 7 2- anions, as well as selective CO 2 capture over CH 4 ., (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The reaction of N-rich pyrazinyl triazolyl carboxyl ligand 3-(4-carboxylbenzene)-5-(2-pyrazinyl)-1H-1,2,4-triazole (H2 cbptz) with MnCl2 afforded 3D cationic metal-organic framework (MOF) [Mn2 (Hcbptz)2 (Cl)(H2 O)]Cl⋅DMF⋅0.5 CH3 CN (1), which has an unusual (3,4)-connected 3,4T1 topology and 1D channels composed of cavities. MOF 1 has a very polar framework that contains exposed metal sites, uncoordinated N atoms, narrow channels, and Cl(-) basic sites, which lead to not only high CO2 uptake, but also remarkably selective adsorption of CO2 over N2 and CH4 at 298-333 K. The multiple CO2 -philic sites were identified by grand canonical Monte Carlo simulations. Moreover, 1 shows excellent stability in natural air environment. These advantages make 1 a very promising candidate in post-combustion CO2 capture, natural-gas upgrading, and landfill gas-purification processes., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Just add water: The copolymerization of propylene oxide and CO2 catalyzed by a cobalt complex is tolerant to the addition of water as chain-transfer reagent to afford polyols (HO-(PPC)-OH) with narrow molecular weight distributions (see picture; PPC=poly(propylene carbonate); PLA=polylactide). The addition of an organocatalyst to these polyols in the presence of lactides produces well-defined triblock copolymers (PLA-b-PPC-b-PLA)., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A large amount of interesting information on the alternating copolymerization of CO2 with terminal epoxides has already been reported, such as the regiochemistry of epoxide ring-opening and the stereochemistry of the carbonate unit sequence in the polymer chain. Moreover, the microstructures of CO2 copolymers from propylene oxide and cyclohexene oxide have also been well-studied. However, the microstructure of the CO2 copolymer from styrene oxide (SO), an epoxide that contains an electron-withdrawing group, has not yet been investigated. Herein, we focus on the spectroscopic assignment of the CO2 copolymer from styrene oxide at the diad level by using three kinds of model dimer compounds, that is, T-T, H-T, and H-H. By comparing the signals in the carbonyl region, we concluded that the signals at δ=154.3, 153.8, and 153.3 ppm in the (13)C NMR spectrum of poly(styrene carbonate) were due to tail-to-tail, head-to-tail, and head-to-head carbonate linkages, respectively. Moreover, various isotactic and syndiotactic model compounds based on T-T, H-T, and H-H (dimers (R,R)-T-T, (S,S)-T-T, and (R,S)-T-T; (R,R)-H-T, (S,S)-H-T, and (R,S)-H-T; (R,R)-H-H, (S,S)-H-H, and (R,S)-H-H) were synthesized for the further spectroscopic assignment of stereospecific poly(styrene carbonate)s. We found that the carbonate carbon signals were sensitive towards the stereocenters on adjacent styrene oxide ring-opening units. These discoveries were found to be well-matched to the microstructures of the stereoregular poly(styrene carbonate)s that were prepared by using a multichiral Co(III)-based catalyst system., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A green and efficient method for large-scale preparation of glycyrrhizic acid from licorice roots was developed by combination of polyamide and macroporous resin. The entire preparation procedure consisted of two simple separation steps. The first step is to use polyamide resin to remove licorice flavoniods from the licorice crude extract. Subsequently, various macroporous resins were tried to purify glycyrrhizic acid, and HPD-400 showed the most suitable adsorption and desorption properties. Under the optimized conditions, a large-scale preparation of glycyrrhizic acid from licorice roots was carried out. A 20 kg raw material produced 0.43 kg of glycyrrhizic acid using green aqueous ethanol as the solvent. The purity of glycyrrhizic acid was increased from 11.40 to 88.95% with a recovery of 76.53%. The proposed method may be also extended to produce large-scale other triterpenoid saponins from herbal materials., (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)