Lithium hexamethyldisilazide/triethylamine-mediated ketone enolization: remarkable rate accelerations stemming from a dimer-based mechanism.

Lithium hexamethyldisilazide/triethylamine-mediated ketone enolization: remarkable rate accelerations stemming from a dimer-based mechanism. Research Abstract Details 

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Lithium hexamethyldisilazide/triethylamine-mediated ketone enolization: remarkable rate accelerations stemming from a dimer-based mechanism. Abstract Text:

Pinjing Zhao,David B Collum,

Mechanistic studies of the enolization of 2-methylcyclohexanone mediated by lithium hexamethyldisilazide (LiHMDS; TMS2NLi) in toluene and toluene/triethylamine (Et3N) mixtures are described. Structural studies of LiHMDS/ketone mixtures in toluene reveal cyclic dimer (TMS2NLi)2(ketone). Rate studies using in situ IR spectroscopy show the enolization proceeds via a dimer-based transition structure, [(TMS2NLi)2(ketone)]. NMR spectroscopic studies of LiHMDS/ketone mixtures in the presence of relatively unhindered trialkylamines such as Me2NEt reveal the quantitative formation of cyclic dimers of general structure (TMS2NLi)2(Et3N)(ketone). Rate studies trace a >3000-fold rate acceleration to a dimer-based transition structure, [(TMS2NLi)2(Et3N)(ketone)].

Lithium hexamethyldisilazide/triethylamine-mediated ketone enolization: remarkable rate accelerations stemming from a dimer-based mechanism. Publishing Authors By Initials

P Zhao,DB Collum,

For similar inorganic chemicals: silicon compounds: silanes research abstracts see: inorganic chemicals: silicon compounds: silanes research

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Lithium hexamethyldisilazide/triethylamine-mediated ketone enolization: remarkable rate accelerations stemming from a dimer-based mechanism. Journal Published:

PUBLICATION TYPE: Research Support, U.S. Gov't,

Journal: Journal of the American Chemical Society

VOLUME: 125

Page Numbers: 4008-9

Journal Abbreviation: J. Am. Chem. Soc.

ISSN: 0002-7863

DAY: 9

MONTH: Apr

YEAR: 2003

Lithium hexamethyldisilazide/triethylamine-mediated ketone enolization: remarkable rate accelerations stemming from a dimer-based mechanism. Information

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LANGUAGE: eng

NlmUniqueID: 7503056

Lithium hexamethyldisilazide/triethylamine-mediated ketone enolization: remarkable rate accelerations stemming from a dimer-based mechanism. Keywords Mesh Terms:

KEYWORDS: Silanes

MESH TERMS: chemistry

Chemical & Substance for Abstract: Lithium hexamethyldisilazide/triethylamine-mediated ketone enolization: remarkable rate accelerations stemming from a dimer-based mechanism. Information

Substance Name: triethylamine

Registry Number: 121-44-8

Grant and Affiliation Information for Lithium hexamethyldisilazide/triethylamine-mediated ketone enolization: remarkable rate accelerations stemming from a dimer-based mechanism.

AFFILIATION: Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853-1301, USA.

Country: United States

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MEDLINETA: J Am Chem Soc

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