Kinetics and Mechanism of the Quinolinium Fluorochromate Oxidation of Some Primary, Secondary and Unsaturated Alcohols in Acetonitrile

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Title:Kinetics and Mechanism of the Quinolinium Fluorochromate Oxidation of Some Primary, Secondary and Unsaturated Alcohols in Acetonitrile
Creators:
Meenakshisundaram, Subbiah
Sockalingam, Ramanathan
Journal or Publication Title:
Collection of Czechoslovak Chemical Communications, 66, 6, pp. 877-896
Uncontrolled Keywords:Solvent effects, Reaction kinetics, Oxidations, Quinolinium fluorochromate, Reaction mechanisms, Chromates, Alcohols, Aldehydes

Abstract

Quinolinium fluorochromate (QFC) in MeCN readily oxidises primary and secondary alcohols to the corresponding carbonyl compounds. Solvent effect on reactivity is quite significant. The reaction can be characterized by the rate equation <i>v</i> = <i>k</i><sub>3</sub><i>K</i><sub>1</sub><i>K</i><sub>2</sub>[Alc][TsOH][QFC]<sub>t</sub>/ {1 + [TsOH](<i>K</i><sub>1</sub> + <i>K</i><sub>1</sub><i>K</i><sub>2</sub>[Alc])}. The ρ* value <i>ca</i> -1.6 is indicative of a partial bonding in the linear transition state envisaged. Large primary kinetic isotope effect (<i>k</i><sup>H</sup>/<i>k</i><sup>D</sup> &gt; 10) in this study suggests a concerted, two-electron hydride transfer mechanism. Mechanistic studies on the oxidation of unsaturated alcohols with QFC in acetonitrile medium described by the rate equation <i>k</i><sub>0</sub> = <i>k</i><sub>2</sub><i>K</i><sub>1</sub>[TsOH]<sup>2</sup> + <i>k</i><sub>4</sub><i>K</i><sub>3</sub><i>K</i><sub>1</sub>[Alc][TsOH] is verified. Product analysis studies rule out the possibility of attack on the double bond. Linear relation in the Exner plots implies the operation of a common mechanism in all the alcohols studied. The high reactivity observed in the cinnamyl alcohol oxidation can be ascribed to resonance interaction through conjugated double bonds. <p>

Title:Kinetics and Mechanism of the Quinolinium Fluorochromate Oxidation of Some Primary, Secondary and Unsaturated Alcohols in Acetonitrile
Creators:
Meenakshisundaram, Subbiah
Sockalingam, Ramanathan
Uncontrolled Keywords:Solvent effects, Reaction kinetics, Oxidations, Quinolinium fluorochromate, Reaction mechanisms, Chromates, Alcohols, Aldehydes
Divisions:Life and Chemical Sciences > Institute of Organic Chemistry and Biochemistry > Collection of Czechoslovak Chemical Communications
Journal or Publication Title:Collection of Czechoslovak Chemical Communications
Volume:66
Number:6
Page Range:pp. 877-896
ISSN:0010-0765
E-ISSN:1212-6950
Publisher:Institute of Organic Chemistry and Biochemistry
Related URLs:
URLURL Type
http://dx.doi.org/10.1135/cccc20010877UNSPECIFIED
ID Code:1829
Item Type:Article
Deposited On:06 Feb 2009 17:13
Last Modified:06 Feb 2009 16:13

Citation

Meenakshisundaram, Subbiah; Sockalingam, Ramanathan (2001) Kinetics and Mechanism of the Quinolinium Fluorochromate Oxidation of Some Primary, Secondary and Unsaturated Alcohols in Acetonitrile. Collection of Czechoslovak Chemical Communications, 66 (6). pp. 877-896. ISSN 0010-0765

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