A simple and mild protocol for copper-catalyzed bromination of quinoline at the C5 site of quinoline by anodic oxidation was developed, affording the desired remote C–H activation products with isolated yields of up to about 90%. The reaction proceeds with low-cost NH4Br and shows mild and green conditions (electricity as a green oxidant; NH3 and H2 as byproducts). At the same time, a gram-scale bromination reaction was also successfully fulfilled, showing its potential applicable value in organic synthesis. Moreover, the CV chart further demonstrated the proposed catalytic cycle.

In this letter, an efficient one-pot asymmetric sequential reaction is achieved by organo/transition metal relay catalysis in constructing two consecutive C−C bonds, which involves enantioselective amino squaramide catalytic Mannich-type addition of pyrazolones to isatin-derived ketimines and a subsequent palladium catalyzed diastereoselective allylic alkylation of pyrazolones with allylic acetates. An array of novel pyrazolone− aminooxindole−propylene structural motifs are obtained in a high level of yield and with excellent enantio-and diastereoselectivity (up to 95% yield, >20:1 dr, >99% ee). This methodology features the formation of vicinal quarternary carbon-stereocenters, and the second all-carbon tetrasubstituted stereogenic center is induced by joint action of the achiral palladium catalysis and the chiral environment generated from the Mannich step. Moreover, the usefulness of this methodology is highlighted by converting the allylic product into the carbonyl compound.