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Covalent organic frameworks (COFs) as a new type of photocatalysts have shown unique advantages in visible-light-driven hydrogen evolution, while the reported overall water-splitting systems are still very rare among various COF-based photocatalysts. Herein, two COFs are integrated to construct a type of organic S-scheme heterojunction for improved overall water splitting. In this system, TpBpy-COF and COF-316 serve as H 2 - and O 2 -evolving components, respectively, which are combined through π-π interaction between conjugated aromatic rings. By introducing ultra-small Pt nanoparticles (NPs) into the pores of the TpBpy-COF nanosheets (NS), the resultant COF-316/Pt@TpBpy-COF NS heterostructure achieves extremely high H 2 and O 2 evolution rates of 220.4 and 110.2 µmol g -1  h -1 , respectively, under visible light irradiation (λ ≥ 420 nm). The results of transient absorption spectra (TAS) and photoelectronic measurements indicate that the organic heterojunction interface notably facilitates the separation and transfer of photogenerated electron-hole pairs. Further, theoretical calculations and in situ experiments confirm the spontaneous formation of the COF/COF heterojunction interface and the active sites for overall water splitting., (© 2024 Wiley‐VCH GmbH.)

Directly converting CO 2 in flue gas using artificial photosynthetic technology represents a promising green approach for CO 2 resource utilization. However, it remains a great challenge to achieve efficient reduction of CO 2 from flue gas due to the decreased activity of photocatalysts in diluted CO 2 atmosphere. Herein, we designed and synthesized a series of dual metallosalen-based covalent organic frameworks (MM-Salen-COFs, M: Zn, Ni, Cu) for artificial photosynthetic diluted CO 2 reduction and confirmed their advantage in comparison to that of single metal M-Salen-COFs. As a results, the ZnZn-Salen-COF with dual Zn sites exhibits a prominent visible-light-driven CO 2 -to-CO conversion rate of 150.9 μmol g -1  h -1 under pure CO 2 atmosphere, which is ~6 times higher than that of single metal Zn-Salen-COF. Notably, the dual metal ZnZn-Salen-COF still displays efficient CO 2 conversion activity of 102.1 μmol g -1  h -1 under diluted CO 2 atmosphere from simulated flue gas conditions (15 % CO 2 ), which is a record high activity among COFs- and MOFs-based photocatalysts under the same reaction conditions. Further investigations and theoretical calculations suggest that the synergistic effect between the neighboring dual metal sites in the ZnZn-Salen-COF facilitates low concentration CO 2 adsorption and activation, thereby lowering the energy barrier of the rate-determining step., (© 2024 Wiley-VCH GmbH.)

A cascade Nazarov cyclization/dicycloexpansions reaction was developed for the precise synthesis of the angularly fused M/5/N (M=5, 6; N=4-9, 13) tricyclic skeletons. The prioritized expansion of the first ring played a critical role in the transformations, due to the release of ring strain, and the nature of the substituents present on the substrate is another influencing factor. This pioneering cascade reaction features broad substrates scope (33 examples), short reaction time, exceptional yields (up to 95 %), and remarkable regioselectivities (>20 : 1). Exploiting the synthetic application of this cascade reaction, we successfully executed a succinct total synthesis of nominal madreporanone for the first time., (© 2024 Wiley-VCH GmbH.)

Metal-organic frameworks (MOFs) have been widely studied as electrocatalysts, and the research strategy to improve their electrocatalytic oxygen evolution reaction (OER) performance is to modify their structure. In this paper, two-dimensional bimetallic MOFs were constructed to improve electrocatalytic OER performance. Using a mild electrochemical method with Ni and Co as metal sources and 4, 4 '-biphenyl dicarboxylic acid (H 2 BPDC) as ligand, two-dimensional NiCo-BPDC was synthesized and then deposited on a carbon cloth electrode. The results show that NiCo-BPDC/CC possessed a low overpotential of 356 mV at a current density of 20 mA cm -2 with a small Tafel slope of 86 mV dec -1 in 1.0 M KOH solution. The two-dimensional NiCo-BPDC exhibits excellent electrocatalytic OER performance because the coordination of Ni and Co in the material and the interaction of the two-dimensional materials provide a large electrochemically active surface area and expose more metal active sites for OER, thus improving the reaction efficiency and indicating NiCo-BPDC as potential OER electrocatalyst., (© 2023 Wiley-VCH GmbH.)

Artificial photosynthetic diluted CO 2 reduction directly driven by natural sunlight is a challenging, but promising way to realize carbon-resources recycling utilization. Herein, a three-in-one photocatalytic system of CO 2 enrichment, CO 2 reduction and H 2 O oxidation sites is designed for diluted CO 2 reduction. A Zn-Salen-based covalent organic framework (Zn-S-COF) with oxidation and reductive sites is synthesized; then, ionic liquids (ILs) are loaded into the pores. As a result, [Emim]BF 4 @Zn-S-COF shows a visible-light-driven CO 2 -to-CO conversion rate of 105.88 µmol g -1 h -1 under diluted CO 2 (15%) atmosphere, even superior than most photocatalysts in high concentrations CO 2 . Moreover, natural sunlight driven diluted CO 2 reduction rate also reaches 126.51 µmol g -1 in 5 h. Further experiments and theoretical calculations reveal that the triazine ring in the Zn-S-COF promotes the activity of H 2 O oxidation and CO 2 reduction sites, and the loaded ILs provide an enriched CO 2 atmosphere, realizing the efficient photocatalytic activity in diluted CO 2 reduction., (© 2023 Wiley-VCH GmbH.)

Novel asymmetric mono- and dialkylation reactions of α-substituted 2,5-diketopiperazines catalyzed by new chiral spirocyclic-amide-derived triazolium organocatalysts have been developed, resulting in a range of enantioenriched 2,5-diketopiperazine derivatives containing one or two tetrasubstituted carbon stereocenters. The reactions feature high yields (up to 98%), and excellent cis-diastereo- and enantioselectivities (up to >20:1 dr, >99 % ee), and they provide a new asymmetric synthetic approach to important functionalized 2,5-diketopiperazine skeletons. Furthermore, a possible reaction mechanism was proposed based on both control experiments and extensive DFT calculations., (© 2022 Wiley-VCH GmbH.)

Although copper-nitrene has been extensively studied as a versatile active species in various transformations, asymmetric reactions involving copper-nitrene have been limited to the aziridination of olefins. Herein, we report the novel copper-nitrene-catalyzed desymmetric oxaziridination reaction of cyclic diketones with alkyl azides and the subsequent rearrangement of the resulting highly active intermediate, which produces a synthetically challenging chiral bicyclic lactam containing a quaternary carbon center. This procedure not only enriches the copper-nitrene-catalyzed asymmetric reactions, but also provides an alternative strategy to address the inherent challenges of catalytic asymmetric Schmidt reactions. This unique reaction could inspire the investigation of novel copper-nitrene-catalyzed asymmetric transformations and their reaction mechanisms., (© 2021 Wiley-VCH GmbH.)

A tandem Bischler-Napieralski/semipinacol rearrangement reaction has been developed for the purpose of assembling a bis(spirocyclic) indole framework, a privileged structural unit of aspidofractinine-type monoterpenoid indole alkaloids, and was used in combination with a subsequent Mannich reaction to expeditiously construct the central bridged bicyclo[2.2.1]heptane ring system of these molecules with contiguous quaternary centers. The development of this novel strategy culminated in the collective total synthesis of four aspidofractinine alkaloids., (© 2020 Wiley-VCH GmbH.)

An enantioselective aldehyde α-alkylation/semipinacol rearrangement was achieved through organo-SOMO catalysis. The catalytically generated enamine radical cation serves as a carbon radical electrophile that can stereoselectively add to the alkene of an allylic alcohol and initiate ensuing ring-expansion of cyclopropanol or cyclobutanol. This tandem reaction enables the production of a wide range of nonracemic functionalizable α-quaternary-δ-carbonyl cycloketones in high yields and excellent enantioselectivity from simple aldehydes and allylic alcohols. As a key step, the intramolecular reaction was also successfully applied in the asymmetric total synthesis of (+)-cerapicol., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Nanoscale metal-organic frameworks (NMOFs) have proven to be a class of promising drug carriers as a result of their high porosity, crystalline nature with definite structure information, and potential for further functionality. However, MOF-based drug carriers with active tumor-targeting function have not been extensively researched until now. Here we show a strategy for constructing active tumor-targeted NMOF drug carriers by anchoring functional folic acid (FA) molecules onto the metal clusters of NMOFs. Two zirconium-based MOFs, MOF-808 and NH 2 -UiO-66, were chosen as models to reduce to the nanoscale for application as drug carriers, and then the terminal carboxylates of FA molecules were coordinated to Zr 6 clusters on the surfaces of the nanoparticles by substitution of the original formate or terminal -OH ligands. The successful modification with FA was confirmed by solid-state 13 C MAS NMR and UV/Vis spectroscopy and other characterization methods. Drug loading and controlled release behavior at different pH were determined by utilizing the anticancer drug 5-fluorouracil (5-FU) as the model drug. Confocal laser scanning microscopy measurements further demonstrated that 5-FU-loaded FA-NMOFs have excellent targeting ability through the efficient cellular uptake of FA-NMOFs. This work opens up a new avenue to the construction of active tumor-targeted NMOF-based drug carriers with potential for cancer therapies., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Crystalline and porous covalent organic frameworks (COFs) and metal-organic frameworks (MOFs) materials have attracted enormous attention in the field of photocatalytic H 2 evolution due to their long-range order structures, large surface areas, outstanding visible light absorbance, and tunable band gaps. In this work, we successfully integrated two-dimensional (2D) COF with stable MOF. By covalently anchoring NH 2 -UiO-66 onto the surface of TpPa-1-COF, a new type of MOF/COF hybrid materials with high surface area, porous framework, and high crystallinity was synthesized. The resulting hierarchical porous hybrid materials show efficient photocatalytic H 2 evolution under visible light irradiation. Especially, NH 2 -UiO-66/TpPa-1-COF (4:6) exhibits the maximum photocatalytic H 2 evolution rate of 23.41 mmol g -1  h -1 (with the TOF of 402.36 h -1 ), which is approximately 20 times higher than that of the parent TpPa-1-COF and the best performance photocatalyst for H 2 evolution among various MOF- and COF-based photocatalysts., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Total syntheses of the biologically important and structurally unique tetracyclic diterpenes conidiogenone, conidiogenol, and conidiogenone B of the cyclopiane class are reported. The absolute configuration of naturally occurring conidiogenone B was also corrected. The key step of our strategy involved the highly efficient construction of both ring C and the quaternary carbon center shared by rings A and C through a one-step regioselective and diastereoselective cycloenlargement in the form of a semipinacol-type rearrangement. In particular, the desired regioselectivity was made possible by properly adjusting the migratory aptitude of the migrating carbon atom through the introduction of an electron-donating phenylthio group at this position., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A novel and efficient strategy to build α-benzylic quaternary cyclopentanones with excellent enantioselectivities (up to 96 % ee) and high yields (up to 99 % yield) has been developed, and its application demonstrated by the first catalytic asymmetric total synthesis of (-)-1,14-herbertenediol and the formal synthesis of (-)-aphanorphine., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A new chemodosimeter for the highly selective sensing and imaging of biothiols was designed and realized in phosphate-buffered saline solution at pH 7.4 through a fluorescence "off-on" response. A unique mechanism featuring a two-step cascade (biothiols→H2 O) sequence for this remarkable recognition is disclosed for the first time., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

An efficient approach toward the 3/6/6/5-fused tetracyclic skeleton of tenuipesine A has been accomplished. The strategy featured 1) a tandem Mitsunobu and 3,3-rearrangement reaction yielding the key intermediate 7 with two adjacent all-carbon quaternary centers with high d.r.; and 2) a tandem DBDMH-mediated semipinacol rearrangement via a 1,2-oxygen migration of an allylic hemiketal to construct the highly substituted tetrahydropyran ring., (Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Four from one: The four title alkaloids (structures shown in blue box) have been synthesized by using a common versatile intermediate with a 6/5/5 tricyclic skeleton. This tricyclic intermediate could be easily assembled by using an intramolecular carbene addition/cyclization and a Dieckmann condensation/Tsuji-Trost allylation as key steps., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A novel cascade reaction involving oxidative dearomatization/semipinacol rearrangement of indol-2-yl cyclobutanols is explored with N-sulfonyloxaziridine (Davis oxaziridines) as oxidant, generating various 2-spiroquaternary 3-oxindoles in modest to good yields. This method might be useful in the synthesis of indole-based alkaloids bearing 2-spiroquaternary carbon centers. PTS=p-toluenesulfonic acid monohydrate., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A highly chemoselective one-pot reaction has been developed involving a tandem semipinacol rearrangement/oxa-Michael addition sequence in which the in situ generated ketol diene intermediate can be transformed specifically to either the spiro- or fused-dihydrofuran products (see scheme). This one-pot tandem reaction represents a general synthetic methodology for the syntheses of the two different kinds of furan derivatives., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Economic and practical advantages are offered by the iron(III)-catalyzed and air-mediated tandem coupling/hydroarylation/dehydrogenation of simple readily available aldehydes, alkynes, and amines for the synthesis of 2, 4-disubstituted quinolines (see scheme).