Alcohols partial oxidation

Microorganisms Biochemical sym. synthesis Aldehydes from prim, alcohols Partial oxidation... 

Manganese dioxide Azomethines from alcohols Partial oxidation of alcohols... 

Reactions with isocyanuric chloride Ketones from sec. alcohols Partial oxidation s. 14, 317... 

The oxidation of higher alkenes in organic solvents proceeds under almost neutral conditions, and hence many functional groups such as ester or lac-tone[26,56-59], sulfonate[60], aldehyde[61-63], acetal[60], MOM ether[64], car-bobenzoxy[65], /-allylic alcohol[66], bromide[67,68], tertiary amine[69], and phenylselenide[70] can be tolerated. Partial hydrolysis of THP ether[71] and silyl ethers under certain conditions was reported. Alcohols are oxidized with Pd(II)[72-74] but the oxidation is slower than the oxidation of terminal alkenes and gives no problem when alcohols are used as solvents[75,76]. 

Since 1960, the Hquid-phase oxidation of ethylene has been the process of choice for the manufacture of acetaldehyde. There is, however, stiU some commercial production by the partial oxidation of ethyl alcohol and hydration of acetylene. The economics of the various processes are strongly dependent on the prices of the feedstocks. Acetaldehyde is also formed as a coproduct in the high temperature oxidation of butane. A more recently developed rhodium catalyzed process produces acetaldehyde from synthesis gas as a coproduct with ethyl alcohol and acetic acid (83—94). 

Partial oxidation of natural gas or a fuel oil using oxygen may be used to form acetylene, ethylene (qv) and propylene (qv). The ethylene in turn may be partially oxidi2ed to form ethylene oxide (qv) via advantages (/) and (5). A few of the other chemicals produced using oxygen because of advantages (/) and (5) are vinyl acetate, vinyl chloride, perchloroethylene, acetaldehyde (qv), formaldehyde (qv), phthaHc anhydride, phenol (qv), alcohols, nitric acid (qv), and acryhc acid. 

Isopropyl alcohol can be partially oxidized by a noncatalytic, liquid-phase process at low temperatures and pressure to produce hydrogen peroxide [7722-84-1] and acetone (24—26). 

It has also been proposed that under the acidic conditions found ia whiskeys, ethanol reacts with lignin (qv) to reduce an alcohol-soluble form of lignin (ethanol lignin). This can be converted into coniferyl alcohol, which can be oxidized to coniferaldehyde. The partial oxidation of ethanol lignin can produce siaapic and coniferyl alcohols that can be converted to syfingaldehyde and vanillin, respectively (8). 

As experiments at Sun Oil Co. in the early 1930s indicated, there were serious disadvantages associated with alcohol. Wliile alcohol did in fact appear to increase the octane number, it left large amounts of deposits in the engine. Alcohol also vaporized out of the gas tank and engine at rapid rates. And the combustion temperature of the alcohol group is lower than for hydrocarbons because it is already partially oxidized. 

Catalytic partial oxidation of a substituted alcohol to Knoechel (1994)... 

The transformations (1) lead to unstable alkyl nitrates, which can detonate very easily. The reactions (2) lead to more or less complete oxidations of the organic molecule. The formation of aldehydes is purely theoretical since they are more oxidisable than alcohols and therefore are not part of the oxidation process by nitric acid. On the other hand, a ketone can form with a secondary alcohol. With tertiary alcohols, carboxylic acid is the only possible outcome of the partial oxidation, which is caused by the breaking of C-C bonds. When the oxidation is out of control, it is likely to have a complete oxidation. Finally, with heavy metal... 

V.C.8.1. Alkenes and Alcohol Functions. Although TS-1 and other titanosi-licates oxidize alcohols to the corresponding aldehydes and ketones, the rates are suppressed in the presence of compounds containing C=C bonds. CH3OH, for example, is not oxidized at all during epoxidations of alkene reactants. Higher alcohols, however, are partially oxidized. The oxidation of unsaturated alcohols in the presence of TS-1 is shown in Table XVII (193). 

In an enantiomer-differentiating oxidation at a poly-(L-valine)-coated Pb02 anode, rac-2,2-dimethyl-l -phenyl-1 -propanol was partially oxidized leaving 43% optically pure (5)-alcohol [371]. At a TEMPO-modified graphite felt anode rac-1-phenyl-ethanol has been enantioselectively oxidized in the presence of (-[-sparteine leaving 46% of the (/ [-alcohol with 99.6% ee [372]. However, under the same conditions, an exclusive dehydrogenation of (-[-sparteine to the iminium salt without oxidation of the alcohol was found [373]. 

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