ABSTRACT
Parlow and coworkers have developed a scavenging method for the versatile DessMartin oxidation procedure [126]. Reaction of a primary or secondary alcohol with an excess of the Dess-Martin reagent in solution produces an aldehyde or ketone. The excess reagent is usually removed in solution-phase reactions by reduction of the unreacted reagent with sodium thiosulfate followed by aqueous extraction. Parlow and coworkers have developed a thiosulfate resin by simply washing commercial chloride-form Amberlyst A-26 ion exchange resin with thiosulfate (Fig. 34). Treating a crude reaction
solution from a Dess-Martin oxidation with the thiosulfate resin reduces the unreacted Dess-Martin reagent to o-iodobenzoic acid, which can then be efficiently sequestered by any of a number of basic resins. This chemistry was demonstrated on a number of alcohols to produce the corresponding aldehydes or ketones in good yields and excellent purities (>99% in almost all cases as measured by GC/MS and 1H NMR).
