Dess- Martin oxidation

DESS - MARTIN Oxidizing Reagent Oxidation of alcohols to aldehydes or ketones by means of penodinanes. 

The mechanism of the Dess-Martin oxidation involves exchange of the alcohol for acetate, followed by proton removal.30... 

The tricyclic core of spirotryprostatin B can be formed via formation of the dihydropyrrole 325 <2000AGE4596>. Removal of the silyl protecting group of 322, followed by Dess-Martin oxidation, and reaction of the resultant aldehyde with the potassium salt of the diketopiperazine phosphonate 323 led to formation of the enamide 324. 

The Michael addition reaction of the serine-derived oxazolidine 326 with ethyl acrylate gave two products. The major product of the reaction was found to be the bicyclic compound 327, which was formed in 27% yield, accompanied by the unsaturated ester 328. The Dess-Martin oxidation of 327 resulted only in formation of the elimination product, the 7,7a-dihydro-177, 377-pyrrolo[l,2-r ]oxazole 328 (Scheme 46) <2001JOC7555>. 

X = CH(OH)R] to butadienals [166-168] and allenyl ketones [137, 169-171], respectively. Using particularly the Swern or Dess-Martin oxidation methods, very high yields can be achieved [166, 172,173],... 

Only a distillative work-up from an acidic oxidation reaction, for example, delivers 55, which then has to be isomerized by base to obtain 56 [113]. Similar precautions for the synthesis of 55 have been reported recently for a chromium-catalyzed oxidation [114] here again the key is to avoid a base and even a chromatographic workup, as already demonstrated for chromium-free Dess-Martin oxidations [110]. 

Dale, Sir Henry 77 Delay 77 Delay, Jean 77 delocalized orbitals 233 Deniker, Pierre 77 Density Functional Theory 55,228,241,271,278 deposition conditions 168 design of the Sawatzky-Kay apparatus 152 Dess-Martin oxidation 11 detailed atomic-level representation 92 determinant 279 diastereoface selectivity 22,... 

Dess-Martin Oxidation, 53, 1 Desulfonylation reactions, 72, 2 Desulfurization ... 

Notes Selective oxidizing agent. Since a mechanistic requirement of this reagent functioning ability is a complexation with the substrate, it is exceedingly important that only the -OH group binds efficiently. A useful advantage of this oxidation protocol is that it takes place under essentially neutral conditions. See Dess-Martin Oxidation. 

The closely related o-iodylbenzoic acid (IBX) and Dess-Martin oxidations have proved to be effective methods for the synthesis of peptide aldehydes (Table 7, Scheme 6) 9 38 39] 2-Iodobenzoic acid is oxidized by potassium bromate to form 2-iodylbenzoic acid (IBX), which can be used directly for IBX oxidation. IBX can be further treated with acetic anhydride and TosOH at 100 °C for 40 minutes to form the more stable Dess-Martin periodinane reagent 45 46]... 

Scheme 6 Dess-Martin Oxidation of a Peptide Alcohol 391...

The newly released alcohol is then oxidized to aldehyde 14 by the mild method of Dess and Martin (see Chapter 7 for further discussion of the Dess-Martin oxidation). 

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