Synthesis of Quinolines via the Metal-free Visible-Light-Mediated Radical Azidation of Cyclopropenes.

We report the synthesis of quinolines using cyclopropenes and an azidobenziodazolone (ABZ) hypervalent iodine reagent as an azide radical source under visible-light irradiation. Multisubstituted quinoline products were obtained in 34-81% yield. The reaction was most efficient for 3-trifluoromethylcyclopropenes, affording valuable 4-trifluoromethylquinolines.

Azide Radical Initiated Ring Opening of Cyclopropenes Leading to Alkenyl Nitriles and Polycyclic Aromatic Compounds.

We report herein a radical-mediated amination of cyclopropenes. The transformation proceeds through a cleavage of the three-membered ring after the addition of an azide radical on the strained double bond and leads to tetrasubstituted alkenyl nitrile derivatives upon loss of N . With 1,2-diaryl substituted cyclopropenes, this methodology could be extended to a one-pot synthesis of highly functionalized polycyclic aromatic compounds (PACs).

Catalytic Enantioselective Ring-Opening Reactions of Cyclopropanes.

This review describes the development of enantioselective methods for the ring opening of cyclopropanes. Both approaches based on the reaction of nonchiral cyclopropanes and (dynamic) kinetic resolutions and asymmetric transformations of chiral substrates are presented. The review is organized according to substrate classes, starting by the more mature field of donor-acceptor cyclopropanes.

Triazene-Activated Donor-Acceptor Cyclopropanes: Ring-Opening and (3 + 2) Annulation Reactions.

Donor-acceptor cyclopropanes substituted with 3,3-dialkyltriazenyl groups are described herein. The strong electron-donating character of the triazene renders the cyclopropanes highly reactive, allowing for catalyst-free ring-opening reactions with methanol and tetracyanoethylene under mild conditions. The triazene-substituted cyclopropanes could also be used as substrates in Lewis acid catalyzed (3 + 2) annulations with silyl enol ethers.

Synthesis of bicyclo[3.1.0]hexanes by (3 + 2) annulation of cyclopropenes with aminocyclopropanes.

We report the convergent synthesis of bicyclo[3.1.0]hexanes possessing an all-carbon quaternary center a (3 + 2) annulation of cyclopropenes with cyclopropylanilines.

Palladium-Catalyzed Carboamination of Allylic Alcohols Using a Trifluoroacetaldehyde-Derived Tether.

The selective palladium-catalyzed carboamination of allylic alcohols is reported on the basis of the use of an easily introduced trifluoroacetaldehyde-derived tether. Aminoalkynylation reactions were realized using alkynyl bromides and commercially available phosphine ligands. For aminoarylations, a new biaryl phosphine ligand, "Fu-XPhos", was introduced to overcome a competitive Heck pathway.