The combination of Pd(TFA) 2 and an N,N′-disulfonyl bisimidazoline ligand shows high catalytic activity and excellent asymmetric induction in the addition of arylboronic acids to cyclic N-sulfonyl ketimines including benzo[d]isothiazole-1,1-dioxides, benzo[e][1,2,3]oxathiazine-2,2-dioxides, and 1,2,5-thiadiazole-1,1-dioxides, by which three types of chiral quaternary carbon-containing sultams with substantial substitution diversity were synthesized with high yields and excellent enantioselectivities (up to >99% ee). The current catalysis demonstrated a remarkable tolerance to oxygen and thus provided an operationally simple approach for constructing enantioenriched cyclic quaternary stereocenters.

A novel metal-free nitrative bicyclization of 1,7-diynes with tBuONO in the presence of H2O is reported, producing three types of skeletally diverse tricyclic pyrroles such as pyrrolo[3,4-c]quinolines, chromeno[3,4-c]pyrroles and benzo[e]isoindoles...

An asymmetric addition of arylboronic acids to pyrazolinone ketimines is reported using palladium/chiral N,N′‐disulfonyl bisimidazoline (Bim) catalytic system, producing 25 examples of enantioenriched 4‐amino‐5‐pyrazolones bearing one quaternary carbon stereocenter with 60–91% yields and 81–98% ee. The reaction demonstrates remarkable compatibility regarding pyrazolinone ketimines and arylboronic acids, rendering an enantioselective access to chiral aza‐heterocycles bearing α‐tertiary amines.

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