Periodinane

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). 

Perilla ketone — see Ketone, 3-furyl isopentyl Perillene synthesis, 4, 668 Perinones, 1, 327, 337 Periodinane, bromo-synthesis, 1, 571 Periodinane, difluoro-reactions, 1, 571 Periodinanes cyclic... 

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. 

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. 

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

The pure dry acid explodes at 233°C, and violently if confined, possibly <200°C. It is also impact-sensitive, exploding under a hammer blow, or under impact of a 534 g steel ball falling from a height of 1 m. Several of its salts (ammonium, potassium, sodium, silver, barium, calcium and magnesium) are also explosive. The acid is precursor to the Dess-Martin periodinane mild oxidant, and is produced when the latter is treated with water. 

The title compound is produced by treatment of 2-iodylbenzoic acid with acetic anhydride in acetic acid, and has found wide application as a mild oxidant ( Dess-Martin periodinane ) for ly and 2y alcohols. Although it appears not to be sensitive to impact, unlike the precursor acid, both explode violently when heated under confinement. The oxidant, on treatment with water is hydrolysed back to the explosive 2-iodylbenzoic acid. Forethought and caution are advised before using these explosive materials on any scale of working. 

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 second synthesis of crystalline 43 was reported by Mori as summarized in Scheme 62 [93]. The building block (4.R,5S)-A was prepared by an enzymatic process, while another building block C was synthesized via Sharpless asymmetric epoxidation. Coupling of A with C gave D, which was cyclized under Op-polzer s conditions to give crystalline E. When E was oxidized with Dess-Martin periodinane or tetra(n-propyl)ammonium perruthenate or Jones chromic acid, crystalline 43 was obtained. Swern oxidation or oxidation with 2,2,6,6-tetramethylpiperidin-1 -oxyl of E afforded only oily materials. Accordingly, oxidation of E to 43 must be executed extremely carefully. A synthesis of oily 43 was reported by Gil [94]. 

Lindel and co-workers had earlier achieved cyclization of intermediate 166 with 2-iodoxybenzoic acid (IBX, Dess-Martin periodinane) to give 167 (Equation 41), followed by subsequent dehydration and dihydroxylation of G(10)—C(10zz) to an advanced synthetic intermediate <2002TL3699>. 

After successful installation of the first two stereocenters, our attention was focused on elaboration of the terminal alkene in 64 (Scheme 6.9). Treatment with disiamylborane followed by oxidative workup afforded primary alcohol 65 in good yield (70-85 %). A side product containing a mixture of two diastereomers (66) was also observed and resulted from conjugate addition of the alkoxide formed during basic workup onto the unsaturated ester. Maintaining the temperature at 0 °C by a slow, dropwise quench during the oxidative workup was necessary to minimize the amount of the undesired cyclization product (66). Subsequent oxidation of the primary alcohol 65 using Dess-Martin periodinane [28] and a Pinnick oxidation afforded carboxylic acid 67 [29]. 

H2O, EtOH, 90°C) can be overcome by using the Dess-Martin periodinane (DMP) (CH2CI2, 25°C) <06JOC8261>. The reaction probably proceeds via thiyl radical 50, which undergoes 1,5-homolytic radical cyclization followed by aromatization of radical 51 to give 2-arylthiazole 52. 

Several organohypervalent iodine reagents have been used for the oxidation of alcohols and phenols such as iodoxybenzene, o-iodoxybenzoic acid (IBX), bis(trifluoroa-cetoxy)iodobenzene (BTI), and Dess-Martin periodinane etc. But the use of inexpensive iodobenzene diacetate (IBD) as an oxidant, however, has not been fully exploited. Most of these reactions are conducted in high boiling DMSO or toxic acetonitrile media that results in increased burden on the environment. 

Scheme 7-39. Reagents and conditions a PI13PCIIOMC, THF, —78°C (91%). b 1 N HC1 (aq), Nal, dioxane (94% at 90% conversion), c TESC1, pyridine, CH2C12, -30°C (92%). d Dess-Martin periodinane, CH2C12. e Et3N, Eschenmoser s salt (97%).

Acyl nitroso compounds (3, Scheme 7.2) contain a nitroso group (-N=0) directly attached to a carbonyl carbon. Oxidation of an N-acyl hydroxylamine derivative provides the most direct method for the preparation of acyl C-nitroso compounds [10]. Treatment of hydroxamic acids, N-hydroxy carbamates or N-hydroxyureas with sodium periodate or tetra-alkyl ammonium periodate salts results in the formation of the corresponding acyl nitroso species (Scheme 7.2) [11-14]. Other oxidants including the Dess-Martin periodinane and both ruthenium (II) and iridium (I) based species efficiently convert N-acyl hydroxylamines to the corresponding acyl nitroso compounds [15-18]. The Swern oxidation also provides a useful alternative procedure for the oxidative preparation of acyl nitroso species [19]. Horseradish peroxidase (HRP) catalyzed oxidation of N-hydroxyurea with hydrogen peroxide forms an acyl nitroso species, which can be trapped with 1, 3-cyclohexanone, giving evidence of the formation of these species with enzymatic oxidants [20]. 

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