Vinylene-bridged covalent organic frameworks (COFs) have shown great potential for advanced applications because of their high chemical stability and intriguing semiconducting properties. Exploring new functional monomers available for the reticulation of vinylene-bridged COFs and establishing effective reaction conditions are extremely desired for enlarging the realm of this kind of material. In this work, a series of vinylene-bridged two-dimensional (2D) COFs are synthesized by Knoevenagel condensation of tricyanomesitylene with ditopic or tritopic aromatic aldehydes. With use of appropriate secondary amines as catalysts, high-crystalline vinylene-bridged COFs were achieved, exhibiting long-range ordered structures, well-defined nanochannels, high surface areas (up to 1231 m 2 g −1 ), and excellent photophysical properties. Under a low loading amount and short reaction time, they enable aerobic photocatalytic transformation of arylboronic acids to phenols with high efficiency and excellent recyclability. This work demonstrates a new functional monomer, tricyanomesitylene, feasible for the general synthesis of vinylene-bridged COFs with potential application in photocatalytic organic transformation, which instigates further research on such kind of material.

A Brønsted-acid-promoted alkyne benzannulation approach was developed to synthesize the aminosubstituted dibenze[a,j]anthracence derivatives in excellent yields, which were directly converted to fully zigzag-edged polycyclic heteroaromatic hydrocarbons via a nitrogendirected electrophilic borylation. As the dopant in a bluegreen electroluminescent device, the resulted compound exhibited relatively high stability.

In this study, we demonstrated a noble Ag-decorated graphene oxide catalyst (GOSH-Ag) for use in the decarboxylative cycloaddition reaction. The catalyst was easily prepared by depositing Ag nanoparticles on thiolated graphene oxide (GOSH) surfaces. Transmission electron microscopy (TEM) indicated that the nanoparticles were well-dispersed and of a small, approximately 3.7 nm average size. These characteristics resulted in a high surface area, which enhanced the catalytic activity of the supported catalyst. Moreover, it was found that the aggregation of Ag catalysts was inhibited by the strong adhesion between the GOSHs and the Ag nanoparticles during the chemical reactions, thereby permitting their reuse. Indeed, the supported catalyst could easily be separated and recovered from the reaction mixture and reused several times.

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Benzil derivatives such as diaryl 1,2-diketones are synthesized via the direct decarboxylative coupling reaction of aryl propiolic acids and their oxidation. The optimized conditions are that the reaction of aryl propiolic acids and aryl iodides is conducted at 140 °C for 6 h in the presence of 10 mol % CuI/Cu(OTf)2 and Cs2CO3, after which HI (aq) is added and further reacted. The method shows good functional group tolerance toward ester, aldehyde, cyano, and nitro groups. In addition, symmetrical diaryl 1,2-diketones are obtained from aryl iodides and propiolic acid in the presence of palladium and copper catalysts.