Alcohols oxidation with DMSO-based reagents

With DMSO Based Reagents. An alcohol is treated with DMSO, DCC, anhydrous phosphoric acid in what is called Moffatt oxidation. In this way, a primary alcohol can be converted to the aldehyde with no carboxylic acid being produced. 

The oxidation of alcohols to aldehydes or ketones by periodane has several advantages over chromium and DMSO-based oxidants because of its shorter reaction times, higher yields and simplified work up. There is very little overoxidation to the carboxylic acid. It is a practical reagent for the facile and efficient oxidation of benzylic and allylic alcohols. Saturated alcohols are slow in their reactions with it. It oxidizes alcohols in the presence of non-hydroxylic functional groups such as sulfides, enols, ethers, furans and 2°-amides. An example of the DMP oxidation is the oxidation of 3,4,5-trimethoxybenzyl alcohol (7.17) with 7.16 in CH2CI2 to give 94% yield of 3,4,5-trimethoxybenzaldehyde (7.18). 

The oxidation of alcohols is not limited to chromium derivatives, DMSO derivatives, or hypervalent iodine compounds. There are several metal-based reagents that can be very effective, particularly with sensitive functionality. This section will examine several of the more important regents. 

The oxidative effect of the DMSO/PhNCO system on cellulose was confirmed by means of alcoholic model compounds (60, 62, 64) that were neatly oxidized into the corresponding ketones. The presence of the active species, the oxidatively acting sulfonium ylide 66, in the cellulose carbanilation mixture was proven by trapping with two reagents, a tocopherol-based compound (48) and a naphthoquinone (68) that was also used in a facile color test to estimate the degrading effect of certain carbanilation mixtures and conditions on cellulose. 

Polmer-snpported IBX Reagents. Two different phenoxide linked polymer-based IBX reagents have been developed. The silica supported reagent (Poly-IBX) is used in THE The oxidation rate increases relative to DMSO as solvent. The primary alcohol in the cyclohexanol may be oxidized preferentially, and thus avoid formation of the cyclohexanone expected from the secondary alcohol (eq 8). This selectively is retained even with a threefold... 

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