Synthesis of Functionalized Polycyclic Compounds: Rhodium(I)-Catalyzed Intramolecular Cycloaddition of Yne and Ene Vinylidenecyclopropanes

Ruthenium-Catalyzed Intramolecular Allene-alkyne Cascade Cyclization: Access to the Sulfone-cyclopenta[a]naphthalene Core

A ruthenium-catalyzed intramolecular cascade cyclization of allene-alkyne has been achieved. This method offers a streamlined and atom-economical approach for the construction of sulfone bearing 1H-cyclopenta[a]naphthalenes, an important structural scaffold that exists in biologically active compounds. Our approach, backed by mechanistic insights from deuterium labeling, DFT calculations, and potential for reaction scale-up, presents synthetic chemists with an invaluable tool for efficiently producing a distinct carbon framework in a one-pot manner. This protocol is operationally simple, exhibiting a broad substrate scope with consistently high yields.

Hydroxoiridium-Catalyzed Hydroalkylation of Terminal Alkenes with Ureas by C(sp3 )-H Bond Activation

Direct alkylation of a methyl group, on di- and trisubstituted ureas, with terminal alkenes by C(sp³ )-H bond activation proceeded in the presence of a hydroxoiridium/bisphosphine catalyst to give high yields of the corresponding addition products. The hydroxoiridium/bisphosphine complex generates an amidoiridium intermediate by reaction with ureas having an N-H bond.

Selective C(sp2)-C(sp) bond cleavage: the nitrogenation of alkynes to amides

Breakthrough: A novel catalyzed direct highly selective C(sp2)-C(sp) bond functionalization of alkynes to amides has been developed. Nitrogenation is achieved by the highly selective C(sp2)-C(sp) bond cleavage of aryl-substituted alkynes. The oxidant-free and mild conditions and wide substrate scope make this method very practical.