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Reactivity of a Dinuclear Pd(I) Complex [Pd(2)(μ-PPh(2))(μ(2)-OAc)(PPh(3))(2)] with PPh(3): Implications for Cross-Coupling Catalysis Using the Ubiquitous Pd(OAc)(2)/nPPh(3) Catalyst System

[Image: see text] [Pd(I)(2)(μ-PPh(2))(μ(2)-OAc)(PPh(3))(2)] is the reduction product of Pd(II)(OAc)(2)(PPh(3))(2), generated by reaction of ‘Pd(OAc)(2)’ with two equivalents of PPh(3). Here, we report that the reaction of [Pd(I)(2)(μ-PPh(2))(μ(2)-OAc)(PPh(3))(2)] with PPh(3) results in a nuanced dis...

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Autores principales: Scott, Neil W. J., Ford, Mark J., Husbands, David R., Whitwood, Adrian C., Fairlamb, Ian J. S.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: American Chemical Society 2021
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8441971/
https://www.ncbi.nlm.nih.gov/pubmed/34539028
http://dx.doi.org/10.1021/acs.organomet.1c00347
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author Scott, Neil W. J.
Ford, Mark J.
Husbands, David R.
Whitwood, Adrian C.
Fairlamb, Ian J. S.
author_facet Scott, Neil W. J.
Ford, Mark J.
Husbands, David R.
Whitwood, Adrian C.
Fairlamb, Ian J. S.
author_sort Scott, Neil W. J.
collection PubMed
description [Image: see text] [Pd(I)(2)(μ-PPh(2))(μ(2)-OAc)(PPh(3))(2)] is the reduction product of Pd(II)(OAc)(2)(PPh(3))(2), generated by reaction of ‘Pd(OAc)(2)’ with two equivalents of PPh(3). Here, we report that the reaction of [Pd(I)(2)(μ-PPh(2))(μ(2)-OAc)(PPh(3))(2)] with PPh(3) results in a nuanced disproportionation reaction, forming [Pd(0)(PPh(3))(3)] and a phosphinito-bridged Pd(I)-dinuclear complex, namely [Pd(I)(2)(μ-PPh(2)){κ(2)-P,O-μ-P(O)Ph(2)}(κ-PPh(3))(2)]. The latter complex is proposed to form by abstraction of an oxygen atom from an acetate ligand at Pd. A mechanism for the formal reduction of a putative Pd(II) disproportionation species to the observed Pd(I) complex is postulated. Upon reaction of the mixture of [Pd(0)(PPh)(3)] and [Pd(I)(2)(μ-PPh(2)){κ(2)-P,O-μ-P(O)Ph(2)}(κ-PPh(3))(2)] with 2-bromopyridine, the former Pd(0) complex undergoes a fast oxidative addition reaction, while the latter dinuclear Pd(I) complex converts slowly to a tripalladium cluster, of the type [Pd(3)(μ-X)(μ-PPh(2))(2)(PPh(3))(3)]X, with an overall 4/3 oxidation state per Pd. Our findings reveal complexity associated with the precatalyst activation step for the ubiquitous ‘Pd(OAc)(2)’/nPPh(3) catalyst system, with implications for cross-coupling catalysis.
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spelling pubmed-84419712021-09-15 Reactivity of a Dinuclear Pd(I) Complex [Pd(2)(μ-PPh(2))(μ(2)-OAc)(PPh(3))(2)] with PPh(3): Implications for Cross-Coupling Catalysis Using the Ubiquitous Pd(OAc)(2)/nPPh(3) Catalyst System Scott, Neil W. J. Ford, Mark J. Husbands, David R. Whitwood, Adrian C. Fairlamb, Ian J. S. Organometallics [Image: see text] [Pd(I)(2)(μ-PPh(2))(μ(2)-OAc)(PPh(3))(2)] is the reduction product of Pd(II)(OAc)(2)(PPh(3))(2), generated by reaction of ‘Pd(OAc)(2)’ with two equivalents of PPh(3). Here, we report that the reaction of [Pd(I)(2)(μ-PPh(2))(μ(2)-OAc)(PPh(3))(2)] with PPh(3) results in a nuanced disproportionation reaction, forming [Pd(0)(PPh(3))(3)] and a phosphinito-bridged Pd(I)-dinuclear complex, namely [Pd(I)(2)(μ-PPh(2)){κ(2)-P,O-μ-P(O)Ph(2)}(κ-PPh(3))(2)]. The latter complex is proposed to form by abstraction of an oxygen atom from an acetate ligand at Pd. A mechanism for the formal reduction of a putative Pd(II) disproportionation species to the observed Pd(I) complex is postulated. Upon reaction of the mixture of [Pd(0)(PPh)(3)] and [Pd(I)(2)(μ-PPh(2)){κ(2)-P,O-μ-P(O)Ph(2)}(κ-PPh(3))(2)] with 2-bromopyridine, the former Pd(0) complex undergoes a fast oxidative addition reaction, while the latter dinuclear Pd(I) complex converts slowly to a tripalladium cluster, of the type [Pd(3)(μ-X)(μ-PPh(2))(2)(PPh(3))(3)]X, with an overall 4/3 oxidation state per Pd. Our findings reveal complexity associated with the precatalyst activation step for the ubiquitous ‘Pd(OAc)(2)’/nPPh(3) catalyst system, with implications for cross-coupling catalysis. American Chemical Society 2021-08-19 2021-09-13 /pmc/articles/PMC8441971/ /pubmed/34539028 http://dx.doi.org/10.1021/acs.organomet.1c00347 Text en © 2021 American Chemical Society https://creativecommons.org/licenses/by/4.0/Permits the broadest form of re-use including for commercial purposes, provided that author attribution and integrity are maintained (https://creativecommons.org/licenses/by/4.0/).
spellingShingle Scott, Neil W. J.
Ford, Mark J.
Husbands, David R.
Whitwood, Adrian C.
Fairlamb, Ian J. S.
Reactivity of a Dinuclear Pd(I) Complex [Pd(2)(μ-PPh(2))(μ(2)-OAc)(PPh(3))(2)] with PPh(3): Implications for Cross-Coupling Catalysis Using the Ubiquitous Pd(OAc)(2)/nPPh(3) Catalyst System
title Reactivity of a Dinuclear Pd(I) Complex [Pd(2)(μ-PPh(2))(μ(2)-OAc)(PPh(3))(2)] with PPh(3): Implications for Cross-Coupling Catalysis Using the Ubiquitous Pd(OAc)(2)/nPPh(3) Catalyst System
title_full Reactivity of a Dinuclear Pd(I) Complex [Pd(2)(μ-PPh(2))(μ(2)-OAc)(PPh(3))(2)] with PPh(3): Implications for Cross-Coupling Catalysis Using the Ubiquitous Pd(OAc)(2)/nPPh(3) Catalyst System
title_fullStr Reactivity of a Dinuclear Pd(I) Complex [Pd(2)(μ-PPh(2))(μ(2)-OAc)(PPh(3))(2)] with PPh(3): Implications for Cross-Coupling Catalysis Using the Ubiquitous Pd(OAc)(2)/nPPh(3) Catalyst System
title_full_unstemmed Reactivity of a Dinuclear Pd(I) Complex [Pd(2)(μ-PPh(2))(μ(2)-OAc)(PPh(3))(2)] with PPh(3): Implications for Cross-Coupling Catalysis Using the Ubiquitous Pd(OAc)(2)/nPPh(3) Catalyst System
title_short Reactivity of a Dinuclear Pd(I) Complex [Pd(2)(μ-PPh(2))(μ(2)-OAc)(PPh(3))(2)] with PPh(3): Implications for Cross-Coupling Catalysis Using the Ubiquitous Pd(OAc)(2)/nPPh(3) Catalyst System
title_sort reactivity of a dinuclear pd(i) complex [pd(2)(μ-pph(2))(μ(2)-oac)(pph(3))(2)] with pph(3): implications for cross-coupling catalysis using the ubiquitous pd(oac)(2)/npph(3) catalyst system
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8441971/
https://www.ncbi.nlm.nih.gov/pubmed/34539028
http://dx.doi.org/10.1021/acs.organomet.1c00347
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