Iodobenzene diacetate

Che et al. have reported the use of iodobenzene diacetate as an alternative to lead tetraacetate in the original Rees-Atkinson reactions of a relatively narrow range of olefin substrates (primarily styrenes) [11]. 

Scheme 7.33. General process of iodobenzene diacetate-mediated hetero-domino transformation.

Quinoxalines 85 have been prepared by the reaction of diols with benzene-1,2-diamines in the presence of a ruthenium catalyst <06TL5633>. Iodobenzene diacetate has been suggested as a less toxic alternative to lead tetraacetate for the oxidative cyclisation of iminooximes to quinoxaline iV-oxides 86 <06TL4969>. 

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 6.33 Oxidation of alcohols using alumina-supported iodobenzene diacetate.

The second most popular method of oxadiazole preparation starts from acylhydrazones 110, which undergo cyclization usually under the action of oxidizing agents (Br2, PhN02, HgO, iodobenzene diacetate). Also, the use of acetic anhydride can lead to cyclization of compound 110. The cyclization can be supported by microwave irradiation. In particular cases, heating is sufficient to accomplish the reaction. 

Several approaches to the 1,2,3-triazole core have been published in 2000. Iodobenzene diacetate-mediated oxidation of hydrazones 152 led to fused 1,2,3-triazoloheterocycles 153 <00SC417>. Treatment of oxazolone 154 with iso-pentyl nitrite in the presence of acetic acid gave 1,2,3-triazole 155, a precursor to 3-(W-l,2,3-triazolyl)-substituted a,P-unsaturated a amino acid derivatives <00SC2863>. Aroyl-substituted ketene aminals 156 reacted with aryl azides to provide polysubstituted 1,23-triazoles 157 <00HC387>. 2-Aryl-2T/,4/f-imidazo[43-d][l,2,3]triazoles 159 were prepared from the reaction of triethyl AM-ethyl-2-methyl-4-nitro-l//-imidazol-5-yl phosphoramidate (158) with aryl isocyanates <00TL9889>. 

Free or benzo-fused 1,2,3-triazoles 286 have been prepared by iodobenzene diacetate-mediated oxidation of hydrazones 285 (Equation 37) <2000SC417>. 

Alumina-sodium borohydride, reduction of carbonyl compounds with, 16 572-573 Alumina sols, gelation of, 23 77 Alumina-supported iodobenzene diacetate (IBD), 16 570... 

Iodobenzene diacetate (IBD), alumina-supported, 16 570 Iodobromite, 4 304 Iodoethane, 14 376 Iodoform, 14 376... 

Relative rates of sulfide-5-oxidation for thianthrene, its 5-oxide, and its 5,5-dioxide were 6.5 x 10 2.6 x 10 1. For the comparable iodobenzene diacetate conversion of thianthrene 5-oxide into the 5,10-dioxide (8 1, cis trans), a mechanism shown in Eqs. (4) and (5) involving rehybri-... 

I, I-Bis(trif1uoroacetoxy)iodoDbenzene is prepared by dissolving, with heating, a given number of grams of (I,I-diacetoxyiodo)benzene (iodobenzene diacetate, Aldrich Chemical Company, Inc. see also Ovg. Synth., Collect. Vol. V, 1973, 660) in twice that number of milliliters of... 

The above examples report perhaps the most well used routes to imidazo[4,5-3]pyridines however, there are many other less well known methods. For example, treatment of 2,3-diaminopyridines with aryl aldehydes and subsequent oxidation with sulfur affords the corresponding imidazo[4,5-/ ]pyridines in good yield <1996CHEC-II(7)283>. A catalytic Fe(iii)/Fe(ll) redox cycle approach to imidazopyridines has been reported (Equation 33) <2000S1380>. A hypervalent iodine oxidative rearangement of 2-aminopyridinecarboxamides has also been reported <2001S541>. Treatment of 2-amino-4,6-diphenyl-3-pyridinecarboxamide 123 with iodobenzene diacetate (IBD) in KOH/MeOH afforded the pyridin-2-one 124 (Equation 34). 

The same group has reported a mild and efficient synthesis of related compounds, l,2,4-triazolo[4,3- ][l,8]naphthyr-idines, using iodobenzene diacetate in the solid state <2002SC2377>. 

Unsymmetrical cycloadducts are produced as a mixture of syii- and 7 //-isomers in good yield by the addition of dienes to monobenzynes generated sequentially from l,2,4,5-tetrakis(trimethylsilyl) benzene by treatment with iodobenzene diacetate (Equation (100) Table 9) <1998J(P1)3921>. 

A wide variety of sulfonyl or carboxyl amides can be applied as nitrogen sources and nontoxic iodobenzene diacetate serves as a mild oxidant. Furthermore, the reaction conditions (e.g., room temperature) are mild, and the imina-tion proceeds with retention of configuration at the stereogenic sulfur (as shown in Scheme 2.1.1.3 for the conversion of (R)-14 into (i )-15). Most importantly, sulfoximine derivatives with easy-to-cleave protective groups at the sulfoximine nitrogen are obtainable, which allow access to the synthetically important free NH-sulfoximines (vide infra). 

Iodosobenzene explodes violently at about 220°, so that determinations of the melting point should not be attempted. It may, however, be converted into iodobenzene diacetate in the following manner. Dissolve 2 g. of iodosobenzene in 6 ml. of glacial acetic acid boiling is usually necessary. Cool. The resulting diacetate is readily soluble in acetic acid but is insoluble in ether. Add about 50 ml. of ether in order to precipitate the iodobenzene diacetate. Filter and wash with ether. The yield is... 

Iodine, detection of, 1041, 1042, 1043, 1045 recovery of, 647 Iodine monochloride, 974 5-Iodo-2-ammotoluene, 647 p-Iodoaniline, 647 Iodobenzene, 533, 538, 591, 598 Iodobenzene diacetate, 541 Iodobenzene dichloride, 534, 541 o-Iodobenzoic acid, 760... 

The tetraketone (348), which is tautomeric with the furanone (349), is converted to the pyranone by oxidation with iodobenzene diacetate (Scheme 109) (80TL1575). 

Keywords alcohol, iodobenzene diacetate, alumina, microwave irradiation, ketone, aldehyde... 

Keywords sulfide, iodobenzene diacetate, microwave irradiation, sulfoxide... 

Neutral alumina (1.5 g) was thoroughly mixed with iodobenzene diacetate (532 mg, 1.65 mmol) and benzyl phenyl sulfide Id (300 mg, 1.5 mmol) using a pestle and mortar. The adsorbed material was placed in an alumina bath inside the microwave oven and irradiated at 50% power for two successive intervals of 45 s each (with time interval of 3-4 min bath temperature rose to 80-85 °C). The progress of the reaction was monitored by TLC (hexane-ethyl acetate, 7 3, v/v). When the reaction was complete the whole material was directly charged onto a silica gel column which provided iodobenzene on elusion with hexane (100 mL). The fractions eluted by chloroform-hexane (1 1 v/v) provided sulfone (<7% by... 

A mixture of carbonyl compound 1, iodobenzene diacetate (1.5 equiv.), and orga-nosulfonic acid (4.5 equiv.) was placed in a test tube placed inside the alumina bath and irradiated for 10-40 s at ten-second intervals in a domestic microwave oven at full power (600 W). After cooling at room temperature the mixture was extracted with dichloromethane (2x20 mL), washed with H20, and dried over MgS04. The mixture was evaporated and the residue was column chromatographed with ethyl acetate-hexane (1 3) to give the desired a-organosulfonyloxy carbonyl compound 2. 

The addition of chlorine and bromine or the epoxidation of 4,7-dihydro-l,3-dioxepins 46 has already been described in CHEC-II(1996). Treatment of 46c with iodobenzene diacetate and A-aminosuccinimide in MeCN yielded a mixture of exo- and OT -A-amino-substituted aziridinodioxepanes 22c (Scheme 1) <2005AXC705> (cf. Section 13.11.3.2). The diastereomeric mixture was easily separated by column purification of the crude reaction product. 

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