Pauson−Khand Reactions of Electron-Deficient Alkenes

Thioureas as Ligands in the Pd-Catalyzed Intramolecular Pauson−Khand Reaction

“…Importantly, contrary to popular thought, the alkynes attached with electron-deficient groups (entries 5, 6, and 8−10 in Table ) gave better results than other members of the family. The results, to our knowledge, have not been reported so far.…”

Synthesis of Chiral Cyclopentenones

“…Additionally, it is tolerant to a broad variety of functional groups, such as alcohols, ethers, thioethers, esters, nitriles, amines, amides, sulfonamides, etc. Therefore, the transformation has received great attention over the last few decades, and a wide number of records appeared in the literature, including a series of reviews. − The asymmetric versions are efficiently accomplished by applying a number of methods to introduce chirality. Depending on the stereochemistry of the reagents, the protocols can be divided into two general categories based on chiral auxiliaries attached either to the alkene or to the alkyne, or starting from achiral precursors.…”

(Di‐tert‐butylphosphanylethyl)cyclopentadienylnickel Chelates with Alkyl, Alkenyl, Aryl, and Alkynyl Ligands: Hints to Cumulenylidene Resonance Forms

“…(Alkyne)hexacarbonyldicobalt complexes can easily be prepared by treatment of the alkyne with dicobalt octacarbonyl. Such complexes are important in the context of the Pauson–Khand reaction, in which coupling of the alkyne with an alkene results, after CO insertion, in valuable cyclopentenones . Manning et al reported the syntheses of some nonchelate cyclopentadienyl triphenylphosphane alkynyl nickel complexes and performed reactions with dicobaltoctacarbonyl resulting in the formation of trimetallic alkyne hexacarbonyldicobalt complexes with a nickel substituent at the coordinated triple bond , .…”