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Title: Observation of Transition‐Metal–Boron Triple Bonds in IrB 2 O − and ReB 2 O −
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 IrB2Oand ReB2Oand investigated them by photoelectron spectroscopy and quantum‐chemical calculations. The results allow to elucidate the structures and bonding in the two clusters. We find IrB2Ohas a closed‐shell bent structure (Cs,1A′) with BOcoordinated to an Ir≡B unit, (OB)Ir≡B, whereas ReB2Ois 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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Award ID(s):
1763380
NSF-PAR ID:
10160286
Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
59
Issue:
35
ISSN:
1433-7851
Page Range / eLocation ID:
p. 15260-15265
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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