Dess-Martin

The Dess-Martin periodinane ( DMP ) reagent, U,l-tris(acetyloxy)-l,l-dihydro-l,2-benziodoxol-3(l//)-one, has also been used in several complex syntheses for the oxidation of primary or secondary alcohols to aldehydes or ketones, respectively (e.g., M. Nakatsuka, 1990). It is prepared from 2-iodobenzoic add by oxidation with bromic add and acetylation (D.a Dess, 1983). 

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

A vanety of secondary alcohols with terminal trifluoromethyl group are oxidized by the Dess-Martin periodinane reagent [52 57] (equation 48)... 

Wipf and Miller have reported side-chain oxidation of 3-hydroxy amides with the Dess-Martin periodinane, followed by immediate cyclodehydration with triphenylphosphine-iodine, which provides a versatile extension of the Robinson-Gabriel method to substituted oxazoles. Application of this method was used to prepare the oxazole fragment 10 in 55% overall yield from 3-hydroxy amide 8. 

CH2CI2, -78 °C then Ph3P, 25 °C MeMgCi, THF, 0 °C Dess-Martin periodlnane, CH2CI2,25 °C (91% overall)... 

Recently, several one-pot oxidation-Wittig procedures that circumvent the need to isolate the intermediate aldehydes have been developed. Various oxidants, including Swern [52], Dess-Martin periodinane [53], IBX [54], Mn02 [55], and BaMnCU [56], can be used in the presence of stabilized ylides to generate a,(3-unsaturated esters. 

Feringa-butenolide 114, in the presence of Dess-Martin periodinane reagent and 2,6-lutidine, gave the bis-ketone 115 which underwent intramolecular cycloaddition to afford endo-selectively the desired decalin-based lactone 116 (Equation 2.32) [114]. Double activation of butenolidic double bond strongly increases the reactivity of dienophile 115. 

Reaction of (S)-(+)-2-aminobutyrate hydrochloride with ethyl oxalyl chloride followed by replacing of the ethyl ester with amino alcohol, oxidation with Dess-Martin periodinate and cyclization using TFA/TFAA in acetic acid gave the cyclic product, which was further converted to the bromide. Sub-... 

The Dess-Martin reagent can be shock sensitive under some conditions and explode > 200°C. Other hypervalent iodine oxidizing reagents are known, including PhI(OAc)2/TEMPO and PhI(OAc)2 supported on alumina with microwave irradiation. 

C47H74O19 17598-65-1) see Lanatosidc C Dess-Martin periodinane (C,3H,3lO, 87413-09-0) see Tacrolimus dexamethasone... 

Oxidation by the Dess-Martin Reagent. Another reagent that has become important for laboratory synthesis is known as the Dess-Martin reagent,28 which is a hypervalent iodine(V) compound.29 The reagent is used in inert solvents such as chloroform or acetonitrile and gives rapid oxidation of primary and secondary alcohols. The by-product, o-iodosobenzoic acid, can be extracted with base and recycled. 

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

Scheme 12.4 shows several examples of the use of the Dess-Martin reagent. 

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