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Cobalt(II) acetylacetonate complexes bearing a phosphine ligand can be key intermediates or precursors to cobalt‐based catalysts; however, they have been rarely studied, especially from a molecular structure point of view. This work is focused on the understanding of how different phosphines react with Co(acac)2(acac = acetylacetonate). To do so, a variety of analytical tools, including NMR and IR spectroscopy, X‐ray crystallography, mass spectrometry, and elemental analysis, have been used to study the reactions and characterize the isolated products. These results have shown that the monodentate ligand, HPPh2, binds to Co(acac)2weakly and reversibly to produce Co2(acac)4(HPPh2), whereas the bidentate ligand, 1,2‐bis(diphenylphosphino)ethane (dppe), interacts with Co(acac)2more strongly to yield a 1D coordination polymer of Co(acac)2(dppe). 2‐(Dicyclohexylphosphino)methyl‐1 H‐pyrrole (CyPNH), which is a pyrrole‐tethered phosphine, forms an unusual 5‐coordinate cobalt complex, Co(acac)2(CyPNH), in which the pyrrole moiety participates in a bifurcated hydrogen–bonding interaction with the [acac]–ligands. In contrast, another bidentate ligand, 4,5‐bis(diphenylphosphino)‐9,9‐dimethylxanthene (xantphos), fails to react with Co(acac)2, presumably due to its wide bite angle and difficulty in bridging two metals.
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Oxochlorin frameworks confining a β-hydroxyketone moiety
Despite the formal presence of an acac-like moiety, β-oxo-meso-OH-porphyrins do not bind 3d and 4d metal ions at their periphery. This is attributed to the loss of macrocycle aromaticity upon expression of an acac-like chelate.
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- Award ID(s):
- 1800361
- PAR ID:
- 10539774
- Publisher / Repository:
- RSC
- Date Published:
- Journal Name:
- Dalton Transactions
- Volume:
- 53
- Issue:
- 31
- ISSN:
- 1477-9226
- Page Range / eLocation ID:
- 13142 to 13150
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D4DT01386G
