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Deaminative functionalization of aliphatic primary amines has great synthetic utility. Herein, we describe a Ni-catalyzed reductive deaminative cross-electrophile coupling reaction between Katritzky salts and aromatic amides. This work provides examples of the synthesis of various ketones from alkylpyridinium salts, including both primary and secondary alkylamines. Given its mild reaction conditions and high functional group tolerance, this cross-coupling strategy is expected to be useful for late-stage functionalization of complex compounds.

Acetetracenylene-1,2-dione reacted with 3-ethylrhodanine in the presence of piperidine and Hantzsch ester via a Knoevenagel condensation–reduction sequence to give a tetracene–rhodanine adduct. This reduced Knoevenagel product exhibited magenta luminescence with a fluorescence quantum yield of φ = 0.34 and fluorescence lifetime of τ = 13.2 ns in toluene. Electrochemical studies and charge carrier transport measurements revealed ambipolar properties with hole and electron mobilities of 5.1 × 10–7 and 1.6 × 10–4 cm2/(V s), respectively.

Levulinic acid (LA) is one of the most significant cellulose-derived compounds. γ-Valerolactone (GVL) and 1,4-pentanediol (1,4-PDO) are considered to be important chemical intermediates. Direct conversion of LA to GVL and GVL to 1,4-PDO was achieved via chemoselective hydrogenation by supported copper catalysts. We studied the transformation of LA to GVL in water and alcohol, and the pathway of the reaction was also studied. LA was converted to GVL catalyzed by the Cu (30%)-WO3 (10%)/ZrO2-CP-300 catalyst at 413 K in ethanol with 81% yield, while 84% GVL was obtained with the Cu (30%)/ZrO2-OG-300 catalyst in water at 393 K. Furthermore, 1,4-PDO was produced from GVL in excellent selectivities (>90%) using the Cu-TiO2/ZrO2-CP-600 catalyst.

A novel copper-catalyzed regiodivergent alkylboration of alkenes with bis(pinacolato)diboron and alkyl halides has been developed. The regioselectivity of the alkylboration was controlled by subtle differences in the ligand structure. The reaction thus enables the practical, regiodivergent synthesis of two different alkyl boronic esters with complex structures from a single alkene.

An unprecedented Pd-catalyzed regioselective activation of gem-difluorinated cyclopropanes induced by C-C bond cleavage is reported. It provides a general and efficient access to a variety of 2-fluoroallylic amines, ethers, esters, and alkylation products in high Z-selectivity, which are important skeletons in many biologically active molecules. In addition, the transformation represents the first general application of gem-difluorinated cyclopropanes as reaction partners in transition-metal-catalyzed cross-coupling reaction.

An example of Rh-catalyzed C–H activation with methyl trifluoroacrylate for the synthesis of fluoroolefins and heterocycles (benzoindolizines) is reported. The types of products were determined by the directing group. The benzoindolizines and fluoroolefins were obtained by using pyridine and pyrazole as the directing group, correspondingly. These transformations present a number of advantages, such as oxidant-free reaction conditions and broad functional group tolerance. Moreover, this reaction greatly extends the application of fluoroolefins.

Cu–Co catalysts, prepared by a co-precipitation method (CP) and an oxalate sol–gel method (OG), can selectively convert furfural (FFA) to cyclopentanone (CPO) or cyclopentanol (CPL), respectively. The conversion of FFA to CPO or CPL by Cu–Co catalysts were studied in aqueous solutions. We found that the product distribution was influenced by the catalyst support, Cu loading, calcination temperature, hydrogen pressure, the number of times the catalyst was reused and the preparation method of the catalyst. The surface morphology, surface area and composition of the catalysts were studied by XRD, XPS, BET, ICP-AES and TEM characterization. We found that there was a strong interaction between Cu and Co. Cu0, Cu2O and Co0 were the main active catalyst phases on the surfaces of the catalysts, but the amounts were different in the different catalysts. Cu0, Co0 and Cu2O were the active hydrogenation species, and Cu2O also played the role of an electrophile or Lewis acid to polarize the CO bond via lone pair electrons on the oxygen atom. According to XRD and XPS, the main phases on the surface of the CP catalysts were Cu0 and Cu2O. The hydrogenation activity of the CP catalyst was relatively weak and the main product was CPO. In contrast, the hydrogenation activity of the OG catalyst was high and the main product was the fully hydrogenated product CPL due to the main active phases of Co0 and Cu2O on the surface of the OG catalyst. At lower hydrogen pressure (2 MPa) and lower Cu loadings (2% for OG, 5% for CP), we obtained the highest yield of 67% CPO and 68% CPL, respectively.

A novel copper-catalyzed regiodivergent alkylboration of alkenes with bis(pinacolato)diboron and alkyl halides has been developed. The regioselectivity of the alkylboration was controlled by subtle differences in the ligand structure. The reaction thus enables the practical, regiodivergent synthesis of two different alkyl boronic esters with complex structures from a single alkene.

A variety of 2-fluoroallylic amines, ethers, esters, and alkylation products are efficiently obtained with high Z-selectivity through regioselective activation of gem-difluorinated cyclopropanes induced by C—C bond cleavage.