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A mild Ru(0)-catalyzed cleavage of C(aryl)–O bonds enabled by a combination of a Ru3(CO)12 catalyst and an imine auxiliary is reported.

Direct functionalization of the C(O)–N amide bond is one of the most high-profile research directions in the last few decades; however oxidative couplings involving amide bonds and functionalization of thioamide C(S)–N analogues remain an unsolved challenge.

An AIE-active Schiff base was available for indicator paper and cell imaging applications for the successive identification of Cu2+ and His.

Herein, we disclose a novel reorganization/cycloaddition between two imine units catalyzed by In(OTf)3 Lewis acid that differs from the well-known [4 + 2] cycloaddition version via the Povarov reaction.

We propose an intramolecular synergistic counteracting strategy of fluorescence resonance energy transfer and the inner filter effect for accurate photoactivation monitoring, to eliminate the influence of the biological microenvironment.

Divergent deaminative and denitrative C–N cleavages and cascade transformations using amines and nitroalkanes have been developed under a highly effective and environmentally-friendly catalytic system (RuCl3/TFE).

We present a general strategy for activation of N–C(S) thioamide bonds by ground-state-destabilization in the context of a full study on transamidation of thioamides with nucleophilic amines.

Chemodivergent control in the functionalization of nitrogen-directed aromatic C–H bonds has been achieved by a switchable catalyst.

A rhodium(III)-catalyzed formal C–H [5 + 1] cyclization of 2-pyrrolyl/indolylanilines with vinylene carbonate has been explored towards the potent assembly of diverse 4-methylpyrrolo[1,2-a]quinoxalines. This established protocol is characterized by an exceedingly simple reaction system, and excellent functional group toleration and yields. Most importantly, entirely distinct from documented [4 + 2] cyclization conversions, herein, the emerging vinylene carbonate firstly presents as a C1 synthon to realize [5 + 1] annulation and shows new chemical reactivity. Biological studies indicate that these prepared products are promising candidates in terms of their antibacterial activity.

A zinc-catalyzed C–H alkenylation of quinoline N-oxides with ynones has been developed to rapidly assemble a broad collection of valuable quinoline-enol organic architectures. Uncommonly, this novel reaction involves C–H functionalization, and N–O, C–C and CC bond cleavage in one operation, and leads exclusively to the formation of an enol rather than a keto product. Application of the enols generated was highlighted by further derivative transformation and preparation of a series of “BODIPY” analogues with high quantum yields (up to 86%).

An acid-functionalized ionic liquid (IL)-catalyzed cascade decarboxylative cyclization of 2-arylanilines with α-oxocarboxylic acids was developed. This approach offered a sustainable and practical pathway to afford a library of quinoxalines in water under ambient conditions. This protocol tolerated various kinds of functional groups and could be easily scaled-up. The developed method featured a recyclable catalytic system, environmentally friendly reaction conditions, simple operation, and a practical workup procedure, which represented the potential to streamline quinoxaline synthesis in industry. A possible mechanism involving a dual activation strategy to promote both decarboxylation and cyclization processes was proposed.

A catalyst-free method for the hydroxylation of arylboronic acids to form the corresponding phenols with sodium perborate as the oxidant was developed using water as the solvent. Under the reaction conditions, the yield of phenol reached 92% at only 5 min. Moreover, the reaction could be conducted without a catalyst under the solvent-free condition, the efficiency of which was as high as that of a liquid-phase reaction. Using a microcalorimeter, the reaction was found to be an exothermic reaction. The reaction mechanism was investigated and understood via DFT calculations, which revealed that it was a nucleophilic reaction.

We developed a general and sustainable approach for the regioselective deoxygenative chalcogenation of 7-azindole N-oxides; the combination of an internal oxidant and a green solvent has been used successfully for the synthesis of mono- and dichalcogenyl 7-azaindoles which are of pharmaceutical interest. The regioselectivity is tunable by the variation of the reaction conditions. I2/PEG was established as an efficient and reusable catalytic system for C–H chalcogenation. This developed methodology has great potential for practical utility, with a broad substrate scope, green reaction conditions, and operational simplicity.

Zanthoxylum bungeanum seed oil (ZSO) cannot be widely consumed because it contains high free fatty acids with an acid value of 73.75 mg KOH per g. Herein, a solid acid catalyst was prepared from ZSO via a carbonization–sulfonation method using concentrated sulfuric acid. The prepared catalyst was characterized by FT-IR, SEM, XPS, XRD, N2 physisorption, and Boehm titration methods. The prepared solid acid was employed as a catalyst to investigate its performance during the simultaneous esterification and transesterification of ZSO in a one-pot process to produce biodiesel. The optimum reaction parameters for obtaining biodiesel in >95% yield using the abovementioned reaction were as follows: 30 : 1 methanol-to-oil molar ratio, a catalyst loading of 8.0 wt%, a reaction temperature of 140 °C, and reaction time of 4.0 h.

A series of VxOy@C catalysts was prepared from different types of biomass and NH4VO3 using a hydrothermal method. The prepared catalysts were characterized using a series of methods including XRD, SEM, FT-IR, SEM and XPS to investigate the mechanism of formation of the VxOy@C catalysts. Furthermore, the factors related to the selectivity of phenol and the mechanism of the hydroxylation of benzene to phenol were studied. It was found that the activity was related to the V species on the catalyst and the selectivity was related to the adsorption of phenol.