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Abstract Reduction of the cobalt(II) chloride complex, Ph2B(tBuIm)2Co(THF)Cl (1) in the presence oftBuN≡C affords the diamagnetic, square planar cobalt(I) complex Ph2B(tBuIm)2Co(C≡NtBu)2(2). This is a rare example of a 16‐electron cobalt(I) complex that is structurally related to square planar noble metal complexes. Accordingly, the electronic structure of2, as calculated by DFT, reveals that the HOMO is largely dz2in character. Complex2is readily oxidized to its cobalt(II) congener [Ph2B(tBuIm)2Co(C=NtBu)2]BPh4(3‐BPh4), whose EPR spectral parameters are characteristic of low‐spin d7with an unpaired electron in an orbital of dz2parentage. This is also consistent with the results of DFT calculations. Despite its 16‐electron configuration and the dz2parentage of the HOMO, the only tractable reactions of2involve one electron oxidation to afford3.
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Second Generation of Cata ‐Annulated Azaacene Bisimides: Towards Electron‐Accepting Materials
Abstract This work presents the 2ndgeneration ofcata‐annulated azaacene bisimides with increased electron affinities (up to −4.38 eV) compared to their consaguine conventional azaacenes. These compounds were synthesized via Buchwald–Hartwig coupling followed by oxidation with MnO2. Crystal structure engineering through variation of the bisimide substituents furnished crystalline derivatives suitable forproof of conceptorganic field effect transistors with electron mobilities up to 2.2×10−4 cm2(Vs)−1. Moreover, we were able to characterize the charge carrying species, the radical anion, using electron paramagnetic resonance and absorption measurements.
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- Award ID(s):
- 1954975
- PAR ID:
- 10416935
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemPlusChem
- Volume:
- 88
- Issue:
- 5
- ISSN:
- 2192-6506
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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