Mechanisms of alcohols

The general mechanism of alcohol oxidation involves coordination of the alcohol at chromium and a rate-determining deprotonation. 

Sakurai et al. have provided what is probably the most important mechanistic finding in the area of intermolecular additions of silenes in recent years, namely a detailed proposal for the mechanism of alcohol addition to the silicon-carbon double bond.68 A cyclic silene 116 was synthesized in the presence of various amounts of methanol and other alcohols, and varying proportions of methanol adducts 117 and 118 were obtained. It was concluded that the methanolysis involved two steps, the first being the association of the oxygen lone pairs with the sp 2-hybridized silicon atom of the silene. The second step, proton transfer, could occur in two ways. If the proton was transferred from the complexed methanol molecule (path a) its delivery would result in syn addition. However, if a second molecule of methanol participated (path b), it would deliver its proton... 

Alcohols are hydroxylated alkyl-compounds (R-OH) which are neutral in reaction due to their unionizable (OH) group (e.g., methanol, ethanol, isopropanol, and w-butanol). The hydroxyl of alcohols can displace water molecules in the primary hydration shell of cations adsorbed onto soil-solid and sediment-solid clay particles. The water molecule displacement depends mainly on the polarizing power of the cation. The other adsorption mechanisms of alcohol hydroxyl groups are through hydrogen bonding and cation-dipole interactions [19,65],... 

Fig. 15.12 (a) Acid-base mechanism of alcohol dehydrogenation. Reprinted with permission from [70], Copyright (1993) Pergamon (Elsevier), (b) Redox mechanism of cyclohexanol ODH. Reprinted with permission from [74]. Copyright (1998) Elsevier. 

Oxidation of Alcohols in a Direct Alcohol Fuel Cell The electrocatalytic oxidation of an alcohol (methanol, ethanol, etc.) in a direct alcohol fuel cell (DAFC) will avoid the presence of a heavy and bulky reformer, which is particularly convenient for applications to transportation and portable electronics. However, the reaction mechanism of alcohol oxidation is much more complicated, involving multi-electron transfer with many steps and reaction intermediates. As an example, the complete oxidation of methanol to carbon dioxide ... 

The conversion of an alcohol to the corresponding ketone or aldehyde is often effected with CrC>3-based oxidants. The general mechanism of alcohol oxidation is outlined below ... 

Oxidation of alcohols is the most frequently reviewed topic for Ru-catalysed oxidations [3-20]. Mechanisms of alcohol oxidation by Ru complexes have been reviewed [21],... 

You M, Crabb DW Recent advances in alcoholic liver disease II. Minireview Molecular mechanisms of alcoholic fatty liver. Am J Physiol Gastrointest Liver Physiol 2004 287 G1. 

McBride, W. J., J. M. Murphy, Gregory J. Gatto, A. D. Levy, K. Yashimoto, Lawrence Lumeng, and Ting K. Li. 1993a. "CNS Mechanisms of Alcohol Self-Administration." Alcohol and Alcoholism 2 suppll 463-67. 

From these spectroscopic and kinetic analyses, the authors proposed a mechanism of alcohol addition to 52 which is similar to one proposed earlier75. 

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