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Abstract Multiple bonds between boron and transition metals are known in many borylene (:BR) complexes via metal dπ→BR back‐donation, despite the electron deficiency of boron. An electron‐precise metal–boron triple bond was first observed in BiB2O−[Bi≡B−B≡O]−in which both boron atoms can be viewed as sp‐hybridized and the [B−BO]−fragment is isoelectronic to a carbyne (CR). To search for the first electron‐precise transition‐metal‐boron triple‐bond species, we have produced IrB2O−and ReB2O−and investigated them by photoelectron spectroscopy and quantum‐chemical calculations. The results allow to elucidate the structures and bonding in the two clusters. We find IrB2O−has a closed‐shell bent structure (Cs,1A′) with BO−coordinated to an Ir≡B unit, (−OB)Ir≡B, whereas ReB2O−is linear (C∞v,3Σ−) with an electron‐precise Re≡B triple bond, [Re≡B−B≡O]−. The results suggest the intriguing possibility of synthesizing compounds with electron‐precise M≡B triple bonds analogous to classical carbyne systems.
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Investigation of Pb–B Bonding in PbB 2 (BO) n − ( n = 0–2): Transformation from Aromatic PbB 2 − to Pb[B 2 (BO) 2 ] −/0 Complexes with BB Triple Bonds
Joint photoelectron spectroscopy and first-principles theory investigations indicate that the Pb-doped PbB2(BO)n−clusters (n= 0−2) undergo a transformation from σ + π doubly aromatic triangle PbB2−to PbB4(BO)2−/0complexes with a B≡B triple bond.
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- Award ID(s):
- 2053541
- PAR ID:
- 10499250
- Publisher / Repository:
- RSC
- Date Published:
- Journal Name:
- Physical Chemistry Chemical Physics
- Volume:
- 26
- Issue:
- 6
- ISSN:
- 1463-9076
- Page Range / eLocation ID:
- 5356 to 5367
- 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/D3CP02800C
