Dess-Martin periodinane DMP , oxidation

Acetylation of epoxy diol 49 followed by Dess-Martin periodinane [DMP] oxidation afforded epoxyketone 53 in 90% overall yield. Deacetylation of 53 led to the formation of epoxy lactol 54, and PCC oxidation successfully oxidized 54 to give the desired keto-aldehyde 55 in 71% yield. Attempts to go from 49 to 55 directly via a double Swem oxidation were not successful. 

The Dess-Martin periodinane (DMP) oxidation of a-, / -, and 7-hydroxy isoxazoles to the corresponding ketones was easily performed in the presence of the isoxazole ring, as well as other functional groups (Equation 44) <2003SL2213>. 

Benziodoxol-3( 1 ff)-one, l,l,l-tris(acetyloxy)-1,1-dihydro- (Dess-Martin periodinane, DMP) oxidation of alcohols, 134, 328-329 Benzo-anellation procedure, 337 Benzocyclobutenes. See Bicyclo[4.2.0]octa-1,3,5-trienes... 

Our brief exploration of an alternative synthetic route to crinipellins from 35 via dione 48, which was deemed to be a good intermediate for the completion of the synthesis without the protecting group chemistry, turned out to be an ill-fated expedition (Scheme 15). oi-Hydroxylation with Davis reagent (C) followed by Dess-Martin periodinane (DMP) oxidation produced the dione... 

Peltier and Ellman reported on an asymmetric synthesis of 2,4,6-trisubstituted piperidines 258 with excellent stereoselectivity. The starting chiral sullinamide 255 was prepared by the Michael addition of ketimine and a,(3-unsaturated ketone. Treatment of 256 with L-Selectride followed by Dess-Martin periodinane (DMP) oxidation produced iy -A7-sulfinylamino ketone 257 with a high diastereomeric ratio, whereas NaBH4-Ti(OEt)4 reduction of 256 followed by DMP oxidation afforded the anti isomer of 258 with 87 13 diastereomeric ratio. 257 underwent alkylative cyclization by acidic treatment followed by diisobutylaluminum hydride (DIBt L-H) reduction to afford 2,4,6-trisubstituted piperidines 258 with excellent diastereoselectivity (Scheme 40.57). 

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). 

Such reactions are also possible in vitro, as several mild oxidizing agents are at hand nowadays. Thus, the Dess-Martin periodinane (DMP) [50] has been proven to be a versatile and powerful reagent for the mild oxidation of alcohols to the corresponding carbonyl compounds. In this way, a series of new iodine(V)-mediated reactions has been developed which go far beyond simple alcohol oxidation [51], Ni-colaou and coworkers have developed an effective DM P-mediated domino polycy-clization reaction for converting simple aryl amides, urethanes and ureas to complex phenoxazine-containing polycycles. For example, reaction of the o-hydroxy anilide 7-101 with DMP (2 equiv.) in refluxing benzene under exposure to air led to polycycle 7-103 via 7-102 in a yield of 35 % (Scheme 7.28) [52]. 

The kinetics of oxidation of Dess-Martin periodinane (DMP) and its iodoxybenzoic acid (IBX) precursor have been compared to explain their often different selectivities.152 A fast pre-equilibrium produces transient iodic esters, whose axial alkoxy structure for IBX was determined by 1H NMR spectroscopy, which then disproportionate in a rate-limiting maimer to product. As a result, steric effects in alcohol oxidation reflect a balance between opposing effects on equilibrium constants and rate constants for disproportionation. With 1,2-diols DMP gives spirobicyclic... 

Iodine(V) reagents such as Dess-Martin periodinane (DMP) and o-iodoxyben-zoic acid (IBX) are known as general reagents for oxidation of alcohols and have been utilized widely for natural product syntheses. Besides their general use for alcoholic oxidation, recently, the active studies on novel utilization of iodine( V) reagents such as DMP and IBX have been pursued mainly by Nicolaou and coworkers [26]. In particular, the versatile reactivities of anilides (62) with IBX or DMP are interesting and involve unprecedented features as follows. o-Imido-quinones (63) are prepared from 62 by the action of DMP and water. This reaction has been investigated extensively and was found to lead to p-quinones (64)... 

The Dess-Martin Periodinane (DMP), a hypervalent iodine compound, offers selective and very mild oxidation of alcohols to aldehydes or ketones. 

Oxidation of the protected 5-aminoindole 129 with Dess-Martin periodinane (DMP) produced the indole-quinone 130. This methodology was employed in a new total synthesis of the Actinomycetes metabolite BE-10988 (131), which is a promising topoisomerase II inhibitor <02JA2221>. 

Like the Swem oxidation, the Dess-Martin periodinane (DMP) reagent oxidizes primary alcohols to aldehydes and secondary alcohols to ketones without using chromium or other heavy-metal compounds. The reaction with DMP takes place under mild conditions (room temperature, neutral pH) and gives excellent yields. The DMP reagent, which owes its oxidizing ability to a high-valence iodine atom, is a commercially available solid that is easily stored. 

There are many methods for selectively oxidizing an alcohol to the corresponding aldehyde. Of course you have to think about the stability of your molecule when you decide which procedure to choose, but ecological and economic aspects are also very important. Chromium-free oxidations such as Swern conditions or Dess-Martin periodinane (DMP) are preferred over the classic methods that employ Jones reagent, Collins reagent or PCC/PDC. For the mechanism of the here used Swern protocol, see Chapter 5, p. 86. 

One example is Swern oxidation, which uses oxalyl chloride and DMSO and is particularly suitable for the selective oxidation of alcohols to aldehydes or ketones. The disadvantages of this oxidation method are the need for low temperatures, the smell of the dimethyl sulfide formed and the possible oxidation of other heteroatoms. Dess-Martin periodinane (DMP, 5) or iodoxybenzoic acid (IBX, 6) are also common oxidizing agents. The main advantage of these two methods is the short reaction time at room temperature. However, typical problems are the low solubility of IBX and the formation of byproducts. In this context, Finney et al. have reported an interesting procedure avoiding these problems by a variation of the temperature IBX is sufficiently soluble in solvents such as ethyl acetate or dichloromethane at elevated temperatures, whereas it is insoluble in these solvents at room temperature. Because of this, the remaining IBX as well as the IBX-derived byproducts can be separated from the reaction mixture by simple filtration. These reisolated IBX byproducts can then be reoxidized and reused. 

The following Swern oxidation is an inexpensive, mild and fast transformation. It provides aldehydes starting from primary alcohols in the absence of water, exclusively. Other mild oxidation methods for the formation of aldehydes are known Dess-Martin periodinane (DMP), o-iodoxybenzoic acid (IBX), chromium(III) reagents, tetramethylpiperidine 7V-oxide and sodium hypochlorite (TEMPO/NaOCl), tetrapropylammonium perruthenate and N-methylmorpholine 7V-oxide (TPAP/NMO), " and palladium(II)-catalyzed oxidations are reported. ... 

Oxidation of 2-iodobenzoic acid with Oxone (2 KHSO5-KHSO4-K2SO4) furnishes the oxidizing agent o-iodooxybenzoic acid, IBX, a periodinane. (Note IBX is reported to be explosive when heated >130 °C.) Acetylation of IBX with AC2O in the presence of a catalytic amount of TsOH produces the Dess-Martin periodinane, DMP, l,l,l-triacetoxy-l,l-dihydro-l,2-benziodoxol-3(l//)-one, in high yield. 

IBX is the penultimate precursor to the periodinane 1,1,1-triacetoxy-1,1-dihydro-1,2-benziodoxol-3( l//)-one [Dess-Martin periodinane (DMP)]. This is a remarkably successful reagent for the selective oxidation of alcohols to carbonyl compounds.It has an extended shelf life and superior solubility in most organic solvents including chloroform, methylene chloride, acetonitrile, and to a lesser extent hexane and ether. ... 

In modern organic synthesis Dess-Martin periodinane (DMP, structure 800 in Scheme 3.316) has emerged as the reagent of choice for the oxidation of primary and secondary alcohols to the respective carbonyl compounds. DMP is commercially available or can be conveniently prepared by the reaction of IBX with acetic anhydride (Section 2.2.3.2) [1211]. The synthetic applications of DMP have been summarized in several overviews [1102,1104,1212,1213]. 

Several research groups have used ionic liquids for the oxidation of alcohols with o-iodoxybenzoic acid (IBX) or Dess-Martin periodinane (DMP). Alcohols undergo smooth oxidation with IBX or with DMP in hydrophilic [bmim]BF4 (structure 36, Figure 6.2) and hydrophobic [bmimjPFe (structure 37) ionic liquids at room temperature under mild conditions to afford the corresponding carbonyl compounds in excellent yields with high selectivity [54]. Similar results were obtained for the oxidation of alcohols with IBX and DMP using ionic liquid [bmim]Cl (l-butyl-3-methyUmidazoliumchloride) [55,56]. IBX- and DMP-promoted oxidations are faster in ionic liquids compared to conventional solvents such as DMSO, DMF, ethyl acetate and water. Recovery of the by-product iodosobenzoic acid is especially simple in ionic liquids. The recovered ionic liquids can be recycled in subsequent reactions with consistent activity. 

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