The role of iodide promoters and the mechanism of ethylene carbonylation catalyzed by molybdenum hexacarbonyl

Chieh Chao Yang, Beata A. Kilos, David G. Barton, Eric Weitz, Justin M Notestein

Research output: Contribution to journalArticle

8 Citations (Scopus)

Abstract

In limited prior reports, molybdenum hexacarbonyl has been shown to be active in catalyzing ethylene carbonylation promoted by ethyl iodide. Here, we assess the productivity of this reaction with respect to various reaction parameters and provide an understanding of the mechanism by NMR and mass spectrometric studies of isotopically labeled reactants. 13C labeled reactants show that ethyl iodide promotes initiation but is not a participant in the primary catalytic cycle, in contrast to classical mechanisms for alcohol carbonylation with an iodide co-catalyst, such as in the Monsanto process. NMR spectroscopy shows incorporation of only one D from D2O into the carbon backbone of propionic acid products, and in a manner consistent with direct, reversible addition of ethylene to a Mo hydride intermediate. CO migratory insertion and a formal hydroxylation then yield propionic acid. Under the conditions described here, the overall cycle gives propionic acid in high selectivity and requiring low promoter loads.

Original languageEnglish
Pages (from-to)211-219
Number of pages9
JournalJournal of Catalysis
Volume319
DOIs
Publication statusPublished - 2014

Fingerprint

Carbonylation
propionic acid
Propionic acid
Iodides
iodides
Molybdenum
molybdenum
Ethylene
ethylene
Hydroxylation
nuclear magnetic resonance
cycles
Carbon Monoxide
productivity
Hydrides
Nuclear magnetic resonance spectroscopy
hydrides
insertion
alcohols
Alcohols

Keywords

  • Carbonylation
  • Ethylene
  • Homogeneous catalysis
  • Isotopic labeling
  • Metal carbonyl
  • Molybdenum
  • Promotion

ASJC Scopus subject areas

  • Catalysis
  • Physical and Theoretical Chemistry

Cite this

The role of iodide promoters and the mechanism of ethylene carbonylation catalyzed by molybdenum hexacarbonyl. / Yang, Chieh Chao; Kilos, Beata A.; Barton, David G.; Weitz, Eric; Notestein, Justin M.

In: Journal of Catalysis, Vol. 319, 2014, p. 211-219.

Research output: Contribution to journalArticle

Yang, Chieh Chao ; Kilos, Beata A. ; Barton, David G. ; Weitz, Eric ; Notestein, Justin M. / The role of iodide promoters and the mechanism of ethylene carbonylation catalyzed by molybdenum hexacarbonyl. In: Journal of Catalysis. 2014 ; Vol. 319. pp. 211-219.
@article{148e08dc08ce4eee86c1f5902107bdc2,
title = "The role of iodide promoters and the mechanism of ethylene carbonylation catalyzed by molybdenum hexacarbonyl",
abstract = "In limited prior reports, molybdenum hexacarbonyl has been shown to be active in catalyzing ethylene carbonylation promoted by ethyl iodide. Here, we assess the productivity of this reaction with respect to various reaction parameters and provide an understanding of the mechanism by NMR and mass spectrometric studies of isotopically labeled reactants. 13C labeled reactants show that ethyl iodide promotes initiation but is not a participant in the primary catalytic cycle, in contrast to classical mechanisms for alcohol carbonylation with an iodide co-catalyst, such as in the Monsanto process. NMR spectroscopy shows incorporation of only one D from D2O into the carbon backbone of propionic acid products, and in a manner consistent with direct, reversible addition of ethylene to a Mo hydride intermediate. CO migratory insertion and a formal hydroxylation then yield propionic acid. Under the conditions described here, the overall cycle gives propionic acid in high selectivity and requiring low promoter loads.",
keywords = "Carbonylation, Ethylene, Homogeneous catalysis, Isotopic labeling, Metal carbonyl, Molybdenum, Promotion",
author = "Yang, {Chieh Chao} and Kilos, {Beata A.} and Barton, {David G.} and Eric Weitz and Notestein, {Justin M}",
year = "2014",
doi = "10.1016/j.jcat.2014.09.008",
language = "English",
volume = "319",
pages = "211--219",
journal = "Journal of Catalysis",
issn = "0021-9517",
publisher = "Academic Press Inc.",

}

TY - JOUR

T1 - The role of iodide promoters and the mechanism of ethylene carbonylation catalyzed by molybdenum hexacarbonyl

AU - Yang, Chieh Chao

AU - Kilos, Beata A.

AU - Barton, David G.

AU - Weitz, Eric

AU - Notestein, Justin M

PY - 2014

Y1 - 2014

N2 - In limited prior reports, molybdenum hexacarbonyl has been shown to be active in catalyzing ethylene carbonylation promoted by ethyl iodide. Here, we assess the productivity of this reaction with respect to various reaction parameters and provide an understanding of the mechanism by NMR and mass spectrometric studies of isotopically labeled reactants. 13C labeled reactants show that ethyl iodide promotes initiation but is not a participant in the primary catalytic cycle, in contrast to classical mechanisms for alcohol carbonylation with an iodide co-catalyst, such as in the Monsanto process. NMR spectroscopy shows incorporation of only one D from D2O into the carbon backbone of propionic acid products, and in a manner consistent with direct, reversible addition of ethylene to a Mo hydride intermediate. CO migratory insertion and a formal hydroxylation then yield propionic acid. Under the conditions described here, the overall cycle gives propionic acid in high selectivity and requiring low promoter loads.

AB - In limited prior reports, molybdenum hexacarbonyl has been shown to be active in catalyzing ethylene carbonylation promoted by ethyl iodide. Here, we assess the productivity of this reaction with respect to various reaction parameters and provide an understanding of the mechanism by NMR and mass spectrometric studies of isotopically labeled reactants. 13C labeled reactants show that ethyl iodide promotes initiation but is not a participant in the primary catalytic cycle, in contrast to classical mechanisms for alcohol carbonylation with an iodide co-catalyst, such as in the Monsanto process. NMR spectroscopy shows incorporation of only one D from D2O into the carbon backbone of propionic acid products, and in a manner consistent with direct, reversible addition of ethylene to a Mo hydride intermediate. CO migratory insertion and a formal hydroxylation then yield propionic acid. Under the conditions described here, the overall cycle gives propionic acid in high selectivity and requiring low promoter loads.

KW - Carbonylation

KW - Ethylene

KW - Homogeneous catalysis

KW - Isotopic labeling

KW - Metal carbonyl

KW - Molybdenum

KW - Promotion

UR - http://www.scopus.com/inward/record.url?scp=84909643423&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84909643423&partnerID=8YFLogxK

U2 - 10.1016/j.jcat.2014.09.008

DO - 10.1016/j.jcat.2014.09.008

M3 - Article

VL - 319

SP - 211

EP - 219

JO - Journal of Catalysis

JF - Journal of Catalysis

SN - 0021-9517

ER -