Alcohol to carboxylic acids

Figure 3-5. The search for a) oxidations of primary alcohols to carboxylic acids will obtain reaction b) as a hit, although this reaction is in reality a hydrolysis of an ester, c) The correct specification of the query to obtain reactions invoivingthe oxidation of aicohols to carboxyiic acids.

Cr03 catalyzed (1-2 mol % oxidation with NalOg 2.5 equiv) as the reozidant in wet aceteonitrile. oxidized primary alcohols to carboxylic acids. 

Potassium permanganate (KMn04) will also oxidize pri mary alcohols to carboxylic acids What is the oxidation state of manganese in KMn04 ... 

Oxidation of primary alcohols (Section 15.10) Potassium permanganate and chromic acid convert primary alcohols to carboxylic acids by way of the corresponding aldehyde. 

Perhaps the most important reaction of alcohols is their oxidation to carbonyl compounds. Primary alcohols yield either aldehydes or carboxylic acids, secondary alcohols yield ketones, but tertiary alcohols are not normally oxidized. Pyridinium chlorochromate (PCC) in dichloromethane is often used for oxidizing primary alcohols to aldehydes and secondary alcohols to ketones. A solution of Cr03 in aqueous acid is frequently used for oxidizing primary alcohols to carboxylic acids and secondary alcohols to ketones. 

OXIDATION OF PRIMARY ALCOHOLS TO CARBOXYLIC ACIDS WITH SODIUM CHLORITE CATALYZED BY TEMPO AND BLEACH 4-METHOXYPHENYLACETIC ACID... 

Oxidation of Primary Alcohols to Carboxylic Acids or Carboxyiic Esters... 

One feature of this oxidation system is that it can selectively oxidize primary alcohols in preference to secondary alcohols, as illustrated by Entry 2 in Scheme 12.5. The reagent can also be used to oxidize primary alcohols to carboxylic acids by a subsequent oxidation with sodium chlorite.34 Entry 3 shows the selective oxidation of a primary alcohol in a carbohydrate to a carboxylic acid without affecting the secondary alcohol group. Entry 5 is a large-scale preparation that uses NaC102 in conjunction with bleach as the stoichiometric oxidant. 

Alcohol oxidation Alcohol to carboxylic acid Losartan... 

Early electrochemical processes for the oxidation of alcohols to ketones or carboxylic acids used platinum or lead dioxide anodes, usually with dilute sulphuric acid as electrolyte. A divided cell is only necessary in the oxidation of primary alcohols to carboxylic acids if (he substrate possesses an unsaturated function, which could be reduced at the cathode [1,2]. Lead dioxide is the better anode material and satisfactory yields of the carboxylic acid have been obtained from oxidation of primary alcohols up to hexanol [3]. Aldehydes are intermediates in these reactions. Volatile aldehydes can be removed from the electrochemical cell in a... 

Nickel(lll) oxide, prepared from a nickel(ii) salt and sodium hypochlorite, is used for the oxidation of alkanols in aqueous alkali [46]. Residual nickel(Ii) oxide can be re-activated by reaction with sodium hypochlorite. Nickel oxides have also long been used in the manufacture of the positive pole in the Edison nickel-iron rechargeable battery, now largely superseded by die lead-acid accumulator, and in the Jungner nickel-cadmium batteries used as button cells for calculators [47]. Here, prepared nickel oxide is pressed into a holding plate of perforated nickel. Such prepared plates of nickel(lli) oxide have been proposed as reagent for the oxidation, in alkaline solution, of secondary alcohols to ketones and primary alcohols to carboxylic acids [48]. Used plates can be regenerated by anodic oxidation. 

Good selectivity for the oxidation of primary alcohols in the presence of secondary ones can be achieved. By appropriate choice of the reaction conditions, overoxidation of the aldehyde from a primary alcohol to carboxylic acid can be minimized. Kinetic isotope effects in the range of 2 to 3 testify about the relevance of the H+-elimination step upon the overall reactivity . In general, the efficiency of oxidation of alkanols is slightly lower... 

For other examples of alcohol to carboxylic acid oxidations in Ch. 1 cf. 2.3.6. 

In general, the oxidation of primary alcohols to carboxylic acids using T)2-dioxygen metal complexes is rare. To our knowledge, only one report (134) communicates such a process. 

Scheme 7. The steps in the oxidation of primary alcohols to carboxylic acids mediated by the peroxo complex [(triphos)IrCl(T)2-02)]. Although not isolated, experimental evidence indicates that an intermediate with the proposed structure indicated by A in the scheme is present.

Table 1. Selected oxidations of saturated primary alcohols to carboxylic acids at the nickel hydroxide electrode...

Potassium nitrosodisulfonate, 258 other methods Bis(tributyltin) oxide, 41 /-Butyl hydroperoxide-Dichlorotris-(triphenylphosphine)rutheni-um(II), 54 Dibutyltin oxide, 95 Hydrogen hexachloroplatinate(IV)-Copper(II) chloride, 145 4-Methoxy-2,2,6,6-tetramethy 1-1 -oxopiperidinium chloride, 183 of alcohols to carboxylic acids Cetyltrimethylammonium permanganate, 69... 

A special construction, called Swiss-Roll cell [13] (Fig. 22.12), is used for the application of the NiOOH electrode in the oxidation of primary alcohols to carboxylic acids. 

Ruthenium-oxo species (Ru04)2 and (Ru04) oxidize primary alcohols to carboxylic acids and secondary alcohols to ketones. New species (Ru02Cl3)(PPh4) and Ru02(bipy)Cl2 cleanly oxidize a wide range of alcohols to aldehydes and ketones without attack of double bonds.638... 

Ru04 is a very reactive reagent that is employed not only for the oxidation of secondary alcohols to ketones and primary alcohols to carboxylic acids,36 but also to perform the following transformations ... 

Anelli s TEMPO-mediated oxidation can be accelerated by the addition of a quaternary ammonium salt, like Aliquat 336, acting as a phase transfer catalyst. This can be advisable in the oxidation of hindered secondary alcohols but can encourage the over-oxidation of primary alcohols to carboxylic acids.16... 

Immobilized TEMPO has been used for the one-pot oxidation of alcohols to carboxylic acids as well.26 For this purpose TEMPO resin 1 was combined with two ion-exchange resins loaded with chlorite anions and hydrogen phosphate in the presence of catalytic amounts of potassium bromide and sodium hypochlorite in solution. The reaction required work-up for the removal of salts, but tolerated several protecting schemes and afforded pure products in good to excellent yields. The reaction is initiated by catalytic TEMPO oxidation of alcohols to aldehydes driven by dissolved hypochlorite followed by oxidation to the carboxylic acids effected by chlorite. 

Carboxylic acid to benzyl ether 2.1° alcohol to carboxylic acid... 

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