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An unprecedented alkylation reaction of malononitriles with enantioenriched primary allylic amines has been developed in a stereospecific manner through palladium-catalyzed sp(3) C-N bond cleavage without additives at room temperature.

Deep eutectic solvents based on choline chloride–carboxylic acids, as a low-cost effective bifunctional catalyst, were successfully used to catalyze epoxidation of soybean oil with peroxyformic acid as the oxygen supplier under solvent-free conditions. The influence of reaction temperature and time on the epoxidation process evaluated by 1H nuclear magnetic resonance (NMR) quantitative analysis was extensively investigated. The optimal mild conditions were 50 °C and 8 h for choline chloride–oxalic acid dihydrate with 88.80% conversion of double bonds and a high selectivity of 93.86%. Meanwhile, choline chloride–malonic acid at 50 °C for 10 h exhibited better catalytic performance, 90.87% selectivity versus only 83.52% in the choline chloride–citric acid monohydrate system for 8 h. The epoxy products analyzed simultaneously by 1H NMR and the titration method were characterized in Fourier transform infrared, 13C NMR, and thermogravimetric analysis. The results suggested choline chloride–oxalic acid dihydrate with a favorable recyclability was more efficient for the promotion of epoxidation of soybean oil.

In recent years, C–C, C–N, and C–O bonds constructed by C–H functionalization have reached considerable attention due to excellent functional group tolerance, cost‐effectiveness, and atom‐economy. Biaryl compounds are one of the important skeletons in the field of organic chemistry, and have been extensively applied to pharmaceuticals, functional materials, and agrochemicals. However, there have been far fewer reports on C–H functionalization by employing biaryls as substrates. Herein we comprehensively review the C–H functionalization of biaryls including annulation/substitution reactions. The discussion is subdivided according to specific reaction types. In summary, we analyzed the corresponding reaction from the points of view of conditions, directing groups, mechanism, and applications. We hope that this minireview will be beneficial for more synthetic chemists to grasp the design of C–H functionalization of biaryl compounds and enlighten them with more ideas on this issue.