Reactivity and Stability of a Ring-Expanded N-Heterocyclic Carbene Copper(I) Boryl Imidinate

R. S. C. Charman; Thomas Horsley Downie; Thomas H. Jerome; Mary F. Mahon; David J. Liptrot

doi:10.3390/inorganics10090135

Reactivity and Stability of a Ring-Expanded N-Heterocyclic Carbene Copper(I) Boryl Imidinate

R. S. C. Charman, Thomas Horsley Downie, Thomas H. Jerome, Mary F. Mahon, David J. Liptrot

Research output: Contribution to journal › Article › peer-review

3 Citations (SciVal)

Abstract

Frustrated Lewis pairs (FLPs) have evolved from a revolutionary concept to widely applied catalysts. We recently reported the ring-expanded N-heterocyclic carbene supported copper(I) boryliminomethanide, (6-Dipp)CuC(=NtBu)Bpin and noted it reacted with heterocumulenes in a fashion reminiscent of FLPs. We thus set out to explore its reactivity with a range of other substrates known to react with FLPs. This was undertaken by a series of synthetic studies using NMR spectroscopy, mass spectrometry, IR spectroscopy, and single crystal X-ray crystallography. (6-Dipp)CuC(=NtBu)Bpin was investigated for its reactivity towards water, hydrogen, and phenylacetylene. Its solution stability was also explored. Upon heating, (6-Dipp)CuC(=NtBu)Bpin decomposed to (6-Dipp)CuCN, which was characterised by SC-XRD and NMR spectroscopy, and pinBtBu. Although no reaction was observed with hydrogen, (6-Dipp)CuC(=NtBu)Bpin reacted with water to form (6-Dipp)CuC(=N(H)tBu)B(OH)pin, which was structurally characterised. In contrast to its FLP-reminiscent heterolytic cleavage reactivity towards water, (6-Dipp)CuC(=NtBu)Bpin acted as a Brønsted base towards phenyl acetylene generating (6-Dipp)CuCCPh, which was characterised by SC-XRD, IR, and NMR spectroscopy, and HC(=NtBu)Bpin

Original language	English
Article number	135
Journal	Inorganics
Volume	10
Issue number	9
Early online date	7 Sept 2022
DOIs	https://doi.org/10.3390/inorganics10090135
Publication status	Published - 30 Sept 2022

Bibliographical note

Funding Information:
D.J.L. thanks the Royal Society for the support of a University Research Fellowship. We wish to thank the University of Bath and MC for use of their analysis facilities. 2

Funding Information:
This research was funded by the Royal Society, grant number URF\R1\191066. The APC was funded by the kind contribution of MDPI.

Publisher Copyright:
© 2022 by the authors.

Keywords

N-heterocyclic carbene
copper
frustrated Lewis pair

ASJC Scopus subject areas

Inorganic Chemistry

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10.3390/inorganics10090135Licence: CC BY

Cite this

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title = "Reactivity and Stability of a Ring-Expanded N-Heterocyclic Carbene Copper(I) Boryl Imidinate",

abstract = "Frustrated Lewis pairs (FLPs) have evolved from a revolutionary concept to widely applied catalysts. We recently reported the ring-expanded N-heterocyclic carbene supported copper(I) boryliminomethanide, (6-Dipp)CuC(=NtBu)Bpin and noted it reacted with heterocumulenes in a fashion reminiscent of FLPs. We thus set out to explore its reactivity with a range of other substrates known to react with FLPs. This was undertaken by a series of synthetic studies using NMR spectroscopy, mass spectrometry, IR spectroscopy, and single crystal X-ray crystallography. (6-Dipp)CuC(=NtBu)Bpin was investigated for its reactivity towards water, hydrogen, and phenylacetylene. Its solution stability was also explored. Upon heating, (6-Dipp)CuC(=NtBu)Bpin decomposed to (6-Dipp)CuCN, which was characterised by SC-XRD and NMR spectroscopy, and pinBtBu. Although no reaction was observed with hydrogen, (6-Dipp)CuC(=NtBu)Bpin reacted with water to form (6-Dipp)CuC(=N(H)tBu)B(OH)pin, which was structurally characterised. In contrast to its FLP-reminiscent heterolytic cleavage reactivity towards water, (6-Dipp)CuC(=NtBu)Bpin acted as a Br{\o}nsted base towards phenyl acetylene generating (6-Dipp)CuCCPh, which was characterised by SC-XRD, IR, and NMR spectroscopy, and HC(=NtBu)Bpin ",

keywords = "N-heterocyclic carbene, copper, frustrated Lewis pair",

author = "Charman, {R. S. C.} and {Horsley Downie}, Thomas and Jerome, {Thomas H.} and Mahon, {Mary F.} and Liptrot, {David J.}",

note = "Funding Information: D.J.L. thanks the Royal Society for the support of a University Research Fellowship. We wish to thank the University of Bath and MC for use of their analysis facilities. 2 Funding Information: This research was funded by the Royal Society, grant number URF\R1\191066. The APC was funded by the kind contribution of MDPI. Publisher Copyright: {\textcopyright} 2022 by the authors.",

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AU - Charman, R. S. C.

AU - Horsley Downie, Thomas

AU - Jerome, Thomas H.

AU - Mahon, Mary F.

AU - Liptrot, David J.

N1 - Funding Information: D.J.L. thanks the Royal Society for the support of a University Research Fellowship. We wish to thank the University of Bath and MC for use of their analysis facilities. 2 Funding Information: This research was funded by the Royal Society, grant number URF\R1\191066. The APC was funded by the kind contribution of MDPI. Publisher Copyright: © 2022 by the authors.

PY - 2022/9/30

Y1 - 2022/9/30

N2 - Frustrated Lewis pairs (FLPs) have evolved from a revolutionary concept to widely applied catalysts. We recently reported the ring-expanded N-heterocyclic carbene supported copper(I) boryliminomethanide, (6-Dipp)CuC(=NtBu)Bpin and noted it reacted with heterocumulenes in a fashion reminiscent of FLPs. We thus set out to explore its reactivity with a range of other substrates known to react with FLPs. This was undertaken by a series of synthetic studies using NMR spectroscopy, mass spectrometry, IR spectroscopy, and single crystal X-ray crystallography. (6-Dipp)CuC(=NtBu)Bpin was investigated for its reactivity towards water, hydrogen, and phenylacetylene. Its solution stability was also explored. Upon heating, (6-Dipp)CuC(=NtBu)Bpin decomposed to (6-Dipp)CuCN, which was characterised by SC-XRD and NMR spectroscopy, and pinBtBu. Although no reaction was observed with hydrogen, (6-Dipp)CuC(=NtBu)Bpin reacted with water to form (6-Dipp)CuC(=N(H)tBu)B(OH)pin, which was structurally characterised. In contrast to its FLP-reminiscent heterolytic cleavage reactivity towards water, (6-Dipp)CuC(=NtBu)Bpin acted as a Brønsted base towards phenyl acetylene generating (6-Dipp)CuCCPh, which was characterised by SC-XRD, IR, and NMR spectroscopy, and HC(=NtBu)Bpin

AB - Frustrated Lewis pairs (FLPs) have evolved from a revolutionary concept to widely applied catalysts. We recently reported the ring-expanded N-heterocyclic carbene supported copper(I) boryliminomethanide, (6-Dipp)CuC(=NtBu)Bpin and noted it reacted with heterocumulenes in a fashion reminiscent of FLPs. We thus set out to explore its reactivity with a range of other substrates known to react with FLPs. This was undertaken by a series of synthetic studies using NMR spectroscopy, mass spectrometry, IR spectroscopy, and single crystal X-ray crystallography. (6-Dipp)CuC(=NtBu)Bpin was investigated for its reactivity towards water, hydrogen, and phenylacetylene. Its solution stability was also explored. Upon heating, (6-Dipp)CuC(=NtBu)Bpin decomposed to (6-Dipp)CuCN, which was characterised by SC-XRD and NMR spectroscopy, and pinBtBu. Although no reaction was observed with hydrogen, (6-Dipp)CuC(=NtBu)Bpin reacted with water to form (6-Dipp)CuC(=N(H)tBu)B(OH)pin, which was structurally characterised. In contrast to its FLP-reminiscent heterolytic cleavage reactivity towards water, (6-Dipp)CuC(=NtBu)Bpin acted as a Brønsted base towards phenyl acetylene generating (6-Dipp)CuCCPh, which was characterised by SC-XRD, IR, and NMR spectroscopy, and HC(=NtBu)Bpin

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DO - 10.3390/inorganics10090135

M3 - Article

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VL - 10

JO - Inorganics

JF - Inorganics

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M1 - 135

ER -

Reactivity and Stability of a Ring-Expanded N-Heterocyclic Carbene Copper(I) Boryl Imidinate

Abstract

Bibliographical note

Keywords

ASJC Scopus subject areas

Access to Document

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Electrospray Time-of-Flight Mass Spectrometer (Open-Access)

Propulse 500 MHz Nuclear Magnetic Resonance (NMR) Spectrometer (1South)

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Reactivity and Stability of a Ring-Expanded N-Heterocyclic Carbene Copper(I) Boryl Imidinate

Abstract

Bibliographical note

Keywords

ASJC Scopus subject areas

Access to Document

Other files and links

Fingerprint

Equipment

Electrospray Time-of-Flight Mass Spectrometer (Open-Access)

Propulse 500 MHz Nuclear Magnetic Resonance (NMR) Spectrometer (1South)

Cite this