(Distinctive Doe)
10-01-01 17:59
No 219074
(Rated as: excellent)
Oxidation of Alcohols with o-Iodoxybenzoic Acid in DMSO: A New Insight into an Old Hypervalent Iodine Reagent.
J. Org. Chem. (1995), 60(22), 7272-6.
Abstract
The ultracentennial 10-I-4 iodinane oxide IBX (3; o-iodoxybenzoic acid; 1-hydroxy-1,2-benziodoxol-3(1H)-one 1-oxide) represents a new oxidizing reagent that successfully joins to the large family of known oxidants. IBX, in contrast to other valuable oxidants, is inexpensive to prep. and easy to handle, can tolerate moisture and water, and generally gives very good yields. Furthermore, IBX is mild and chemoselective (primary alcs. are converted into aldehydes with no overoxidn. to acids; 1,2-diols are converted to a-ketols or a-diketones without oxidative cleavage; amino alcs. are oxidized to amino carbonyls, without protection of the amino group; sensitive heterocycles are not affected; various other functional groups are compatible with IBX oxidn.). IBX is versatile (it works in various solvents and it is highly sensitive to temp. variations), and its solns. in DMSO are stable enough to carry out the oxidn. reaction easily.
They prepare Cathinone from PPA in the article, I'll post details when I get the full text.
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(Distinctive Doe)
10-01-01 18:03
No 219075
(Rated as: excellent)
CAUTION! IBX is explosive under impact or heating to >200 C.13 Sporadically, IBX did not decompose explosively at 233 C, but melted with browning. However, this cannot be taken as an indication of absence of explosivity since the same batch showed inconsistent results.
Preparation
IBX, 1-Hydroxy-1,2-benziodoxol-3(1H)-one 1-Oxide (1) (95% Purity). 2-Iodobenzoic acid (50.0 g, 0.20 mol) was added all at once to a solution of Oxone (181.0 g, 0.29 mol, 1.3 equiv) in deionized water (650 mL, 0.45 M) in a 2 L flask. The reaction mixture was warmed to 70-73 C over 20 min and mechanically stirred at this temperature for 3 h. The aspect of the mixture varies consistently during the reaction. The initial thick slurry coating the walls of the flask eventually becomes a finely dispersed, easy to stir suspension of a small amount of solid that sedimented easily upon stopping the stirring. The suspension was then cooled to 5 C and left at this temperature for 1.5 h with slow stirring. The mixture was filtered through a medium porosity sintered-glass funnel, and the solid was repeatedly rinsed with water (6 Ч 100 mL) and acetone (2 Ч 100 mL). The white, crystalline solid was left to dry at rt for 16 h and weighed 44.8-45.7 g (79-81%).
Mother and washing liquors were oxidizing and acidic. They were treated with solid Na2SO3 (70 g, 0.55 mol) and neutralized with NaOH (1 M) before disposal. The internal temperature rose to 30 C.
The purity of IBX obtained by this method was 95% (1H NMR, elemental analysis). The remainder was 2-iodosobenzoic (4%) and 2-iodobenzoic (~0.5%) acids, as judged by integration of the triplets at 7.70 and 7.47 ppm, respectively, in the 1H NMR spectrum (ca. 5 mg in 0.5 mL of DMSO-d6).
Mp: 233 C dec (lit.2b mp 232-233 C). Anal. Calcd for C7H5IO4: C, 30.03; H, 1.80; I, 45.32. Found: C, 30.16; H, 1.82; I, 45.32. H2O <0.1% (K.F.). 1H NMR, 13C NMR, and IR spectra all agree with those previously reported.3a
IBX (99% purity, 1H NMR, elemental analysis) was similarly prepared by adding 2-iodobenzoic acid (5.0 g, 0.020 mol) to an Oxone solution in deionized water (37.2 g, 0.061 mol, 3 equiv in 200 mL) in a 0.5 L flask. The suspension was set to 70 C; after 1 h at this temperature a clear solution was obtained that delivered analytical grade IBX upon cooling the solution to 0-5 C for 0.5 h and filtering and washing the crystals as described before (4.4 g, 77%).
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(Distinctive Doe)
10-01-01 18:06
No 219077
(Rated as: excellent)
This is for use in the above synthesis of IBX.
Manufacture of nuclear-iodinated iodine compounds of aromatic character
United States Patent 4,007,221
Urbach February 8, 1977
Preparation of o-iodobenzoic acid
153 parts by weight of concentrated sulfuric acid and 137 parts by weight of anthranilic acid are introduced successively into 500 parts by weight of water in a stirred vessel. A solution of 69 parts by weight of sodium nitrite in 100 parts by weight of water is added to the resulting suspension in the course of about 20 minutes at from 0.degree. to 5.degree. C. The mixture is then stirred for a further 30 minutes at from 0.degree. to 10.degree. C. In another stirred vessel, 166 parts by weight of potassium iodide are dissolved in 375 parts by weight of water and 66 parts by weight of concentrated sulfuric acid and 25 parts by weight of a 40% strength aqueous sodium bisulfite solution are added successively. The diazonium solution is allowed to run into this solution in the course of about 30 minutes, with external cooling, the temperature being kept at from 20.degree. to 40.degree. C. The mixture is then stirred for 30 minutes at about 40.degree. C, after which it is heated at from 70.degree. to 80.degree. C for one hour. After cooling, filtering on a suction filter and washing with 40 parts by weight of water, 242 parts by weight of o-iodobenzoic acid are obtained. Melting point = 160.degree.-162.degree. C. Yield 97% of theory.
If the reaction is repeated in the absence of a reducing agent, a blackish brown o-iodobenzoic acid of melting point 145.degree.-150.degree. C is obtained in only 75% yield. During the reaction, iodine vapors form and these partly deposit in the condenser and partly escape from the reactor with the nitrous gases which are also formed. After completion of the reaction, resinous deposits were found on the walls of the stirred vessel.
o-Iodobenzoic acid is an intermediate for the manufacture of fungicides. For example, reaction of o-iodobenzoic acid with aniline gives o-iodobenzanilide, which has a good fungicidal action when used in plant protection.
anthranilic acid synthesis is here
https://www.rhodium.ws/chemistry/quaalude.txt
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(Distinctive Doe)
10-01-01 18:58
No 219096
(Rated as: excellent)
Use of potassium bromate: syntheses of iodoxybenzene derivatives.
J. Indian Chem. Soc. (1981), 58(6), 605-7
Abstract
Iodoxybenzenes were prepd. by the oxidn. of various iodobenzene derivs. using KBrO3 under acidic conditions.
And these articles
b) Dess D. B. and Martin J. C., J. Org. Chem., 1983, 48, 4155.
c) Dess B. D. and Martin J. C., J. Am Chem. Soc. 1991, 113, 7277.
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(Distinctive Doe)
10-02-01 22:04
No 219578
(Rated as: excellent)
Preparation of 1-hydroxy-1,2-benziodoxol-3(1H)-one (IBX)
2-Iodobenzoic acid (100 g, 0.40 mol) and 0.73 M H2SO4 (858 mL, made from 34.75 mL conc. H2SO4 diluted to 858 mL) were placed in a two liter three-neck flask which was fitted with a mechanical stirrer. Potassium bromate (89.5 g, 0.54 mol) was added portionwise over 30 min, then the reaction mixture was heated in an oil bath to an internal temperature of 65°C for 1.25 h.
Another portion of potassium bromate (12 g, 0.07 mol) was added followed by additional portions (12 g and 10 g) at 30 min intervals. An aliquot of the solid resting on the bottom of the flask was removed, filtered through a fritted glass funnel and washed successively with water (5 mL), ethanol (5 mL) diethylether (5 mL) and dried on a vacuum line for 5 min.
The 1H NMR spectrum was obtained in DMSO-d6 and analyzed.2 If more than 3% of 1a remained, a final portion of potassium bromate (10 g, 0.06 mol) was added and allowed to react for an additional 30 min. The stirring was continued while the reaction mixture was cooled in an ice bath to an internal temperature of 15°C. The stirring was then stopped and any solid floating on top was decanted to a waste container before collecting the product by filtration in a sintered glass funnel. The filter cake was then washed with water (3 x 500 mL), ethanol (2 x 200 mL) and diethyl ether
(3 x 100 mL). The product was then dried at ambient temperature overnight on a high vacuum line (~0.1 mmHg) to provide IBX (93.3 g, 82%) as a white solid.
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