Synthesis and characterization of new adducts of cobalt bis(2,4-pentanedionate). Molecular structure of a cis complex: cobalt bis(2,4-pentanedionate) N,N,N',N'-tetraethyl-1,2-diaminoethane

Bis(acetato-O)bis[2-(dimethylamino)ethanol-κ2N,O]cobalt(II)

“…Two intramolecular hydrogen bonds link the hydroxy function of each dmaeH group with the non-coordinated O atoms of the acetate groups; the hydrogen bonding parameters are shown in Table 2. All bond lengths and angles are in the expected range and are in agreement with those found for similar complexes such as [Co(acac) 2 (H 2 O)] 2 (Cotton & Elder, 1966), [Co(acac) 2 (teeda)] (Colborn et al, 1988) (van Niekerk & Schoening, 1953). The 'bite' angle of the dmaeH ligand, O-Co-N, is significantly less than 90 at 81.67 (5) , but is closely comparable to that of its nickel counterpart [Ni(CH 3 CO 2 ) 2 (dmaeH) 2 ] (78.60 (5) ), and the Co-O(acetate) bond lengths are slightly shorter than the corresponding Ni ones (Williams et al, 2001).…”

Synthesis and Structural Studies of Two New Base Adducts of Bis(2,4‐pentanedionato)cobalt(II)

“…[12] In this context, it is of interest to probe the stability and reactivity of such adducts and additional information can be gained by contrasting the properties of chelating ligands, constrained to adopt cis geometry, with those of monodentate ligands, which typically yield trans complexes. [13] In this paper, the syntheses, crystal structures and spectroscopic properties of cis-[Co(acac) 2 (Hdmpz) 2 ] (1) and [Co(acac) 2 (Hdmea)] (2) are described. Both complexes are new base adducts of bis(2,4-pentanedionato)cobalt() with Hdmpz (3,5-dimethylpyrazole) or Hdmea (dimethylethanolamine).…”

Well-Defined Cationic Cobalt(I) Precatalyst for Olefin-Alkyne [2 + 2] Cycloaddition and Olefin-Diene Hydrovinylation Reactions: Experimental Evidence for Metallacycle Intermediates

“…Cobalt­(III) (acetylacetonate) complexes were targeted due to the availability of the starting materials and the anticipated air stability of the products. The addition of 1 equiv of dppf to a THF solution of Co­(acac) 2 resulted in a color change from red to purple after 1 h, signaling the formation of (dppf)­Co­(acac) 2 .…”