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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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This content will become publicly available on April 16, 2026
PB and AsB triple bonds in the linear PB 2 O − and AsB 2 O − species
EB2O−(E = P, As) type of clusters are found to have [EB–BO]−closed-shell linear structures with EB triple bonds.
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- Award ID(s):
- 2403841
- PAR ID:
- 10657916
- Publisher / Repository:
- RSC
- Date Published:
- Journal Name:
- Chemical Science
- Volume:
- 16
- Issue:
- 16
- ISSN:
- 2041-6520
- Page Range / eLocation ID:
- 7004 to 7009
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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