The broad diversity of CpCo(I) complexes

Abstract

<jats:title>Abstract</jats:title><jats:p>The presented review will focus on the systematic overview of the available synthetic approaches and the reactivity and the structural characteristics of selected mononuclear CpCo(I) complexes with (non)chelating neutral donor ligands. The complexes containing symmetrical or unsymmetrical neutral ligand combinations aside from the anionic cyclopentadienyl (Cp) ligand will be discussed and the differences to complexes with substituted Cp ligands will be considered in selected cases.</jats:p>

Synthesis, Characterization, and Reactivity of Hydroxycyclopentadienyl Cobalt Complexes

“…Compound 2 is stable at room temperature under a nitrogen atmosphere, but it slowly decomposes under nitrogen above 50 °C. While cyclopentadienyl cobalt biscarbonyl complexes, Cp′Co(CO) 2 , are known to undergo ligand exchange reactions with phosphine and phosphite ligands to form mono-and bissubstituted complexes, 29,31,45 Compounds 3−6 were characterized by 1 H, 31 P, 13 C NMR and elemental analysis. The trends in the carbonyl stretching frequencies (υ(CO): 2, 1951 cm −1 > 6, 1940 cm −1 > 3, 1930 cm −1 > 4, 1929 cm −1 > 5, 1920 cm −1 ) are also in the order of electron donating ability of the substituted ligand according to Tolman's Electronic Parameter 46 (CO < P(OPh) 3 < P(OMe) 3 < P(OEt) 3 < P(OiPr) 3 ).…”

Cobalt Catalysts for [2+2+2] Cycloaddition Reactions: Isolated Precatalysts and in situ Generated Catalysts

“…In cobalt catalysis especially cyclopentadienyl (Cp) cobalt half‐sandwich complexes have found great attention since their first discovery and a large variety of different complexes is known [16] . In the last two decades also in situ generated catalysts have grown from initial applications to sophisticated catalytic systems, enabling unprecedented reactivities and adding novel features to cyclotrimerization reactions.…”

Synthesis and Oligomerization of CpM(CO)2

“…Among group 9 metal complexes, compounds bearing an η 5 -cyclopentadienyl ligand (η 5 -Cp) are the classical ones, which have been extensively utilized in a number of catalytic systems. 1 The representative complexes are formulated as CpM(CO) 2 , i.e., cyclopentadienyl metal(I) dicarbonyl. As such, CpCo(CO) 2 has been employed for catalytic cycloaddition to generate aromatic compounds from corresponding acetylene derivatives.…”