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Herein, we report an asymmetric two-component alkenyl Catellani reaction for the construction of C--N axial chirality through a palladium/chiral norbornene cooperative catalysis and an axial-to-axial chirality transfer process. Various partially aromatic iodinated 2-pyridones, quinolones, coumarin and uracil substrates react with 2,6-disubstituted aryl bromides with a tethered amide group, to afford a wide variety of polycyclic C--N atropisomers (38 examples, up to 97% e.e.). The obtained C--N axial chirality originates from the preformed transient C--C axial chirality with high fidelity. The synthetic utility of this chemistry is demonstrated by facile preparation of complex quinoline and pyridine based C--N atropisomers through a N-deprotection and aromatization sequence. In addition, a remote axial-to-central diastereoinduction process dictated by C--N axial chirality is observed with excellent diastereocontrol. [ABSTRACT FROM AUTHOR]

Through the Cu(I)-catalyzed coupling of diazophosphonates with terminal alkynes, an efficient method for the synthesis of allenylphosphonates has been developed. Simple and inexpensive CuI is used as the catalyst and the reaction is conducted under mild conditions. [ABSTRACT FROM AUTHOR]

A Cu-catalyzed three-component cross-coupling reaction of terminal alkyne, α-diazo ester, and alkyl halide has been developed. This transformation involves sequent migratory insertion of copper-carbene and nucleophilic substitution, in which a C(sp)-C(sp³) bond and a C(sp³)-C(sp³) bond are formed successively on a carbenic center. Michael addition acceptors can also be employed instead of alkyl halides that enable Michael addition to be an alternative way to build C(sp³)-C(sp³) bond. This transformation represents a highly efficient method for the construction of all-carbon quaternary centers. [ABSTRACT FROM AUTHOR]