Iodide salts, extraction

Ewing et al. (2) noted that C. bowiei, a small shrub in New South Wales and southern Queensland and a tree growing to about 10 m (30 feet) in northern Queensland, afforded alkaloids which were different but structurally closely related. Methods of isolation were essentially the same, and the alkaloids were obtained as sparingly soluble iodide salts after addition of potassium iodide. (—)-Cryptaustoline iodide (C20H24NO4I) was obtained from extracts of the bark of larger northern trees, and (-)-cryptowoline iodide (C,gH2oN04l) was found to be present in the smaller southern shrubs. 

Nikolic et al. reported the preparation and coulometric determination of quaternary ammonium iodides of procaine and of other local anesthetics [63]. After extraction from 0.33 M NaOH, the quaternary iodide salts were prepared by precipitation with methyl iodide in ethyl ether. The quaternary iodides were then coulometrically determined with the use of a Radiometer titrator. The method used a silver cathode and anode (in electrolytes of 2 M and 0.4 M H2SO4, respectively), and a reference mercurous sulfate electrode. For drug determinations in the range of 0.12 to 0. 96 mg, the standard deviations were typically found to be 4 to 8 pg. 

With these process factors in mind, a continuous, homogeneous reaction process concept was developed in which the starting epoxide 1 is fed as a liquid to the reactor containing the soluble Lewis acid and iodide salt while continuously removing the 2,5-DHF and crotonaldehyde by distillation. Continuously, or as needed, the catalysts are recovered from the reaction mixture by extraction with an alkane and the undissolved oligomer is discarded. 

The demethylation of the iodide salt Under an inert atmosphere, a solution of 0.40 g N,N,N-trimethyltryptammonium iodide in 5 mL THF was treated with 1.5 mL of 1M LiEt3BH in THF and held at reflux temperature for 9 h. After cooling, the mixture was acidified with dilute HCI and the THF removed under vacuum. The residue was suspended in dilute NaOH and extracted with Et20. The extracts were pooled, and the solvent removed under vacuum to provide a residue of 0.12 g N,N-dimethyltryptamine (DMT) as a crystalline solid, with a mp of 57-59 °C. IR (in cm-1) 732, 740, 811,859, 1011, 1037, 1110, 1171. The MS is discussed below. 

Boiling soln. of the two salts are mixed together, and after cooling, alcohol eq. to 15 per cent, of the water present is added. After standing, the clear liquid is separated from the crystals of potassium sulphate, and evaporated until the ammonium iodide commences to crystallize out, when ammoniacal alcohol is added and the crystals of potassium sulphate again removed. The ammonium iodide can then be separated by crystallization. The ammonium iodide is extracted from the mother liquid by dil. alcohol. 

The demethylation of the iodide salt Under an inert atmosphere, a solution of 0.40 g N,N,N-trimethyltryptammonium iodide in 5 mL THF was treated with 1.5 mLof lMLiEt3BHinTHFandheldatrefluxtemperaturefor9h. Aftercooling, the mixture was acidified with dilute HC1 and the THF removed under vacuum. The residue was suspended in dilute NaOH and extracted with Et20. The extracts were... 

Although several studies have examined the effects of various promoters and ligands on the methanol homologation reaction, none has identified a system with substantially improved selectivity. However, there are many claims that iodide accelerates the rate of the reaction 62-64). While the possible sources of this enhancement have been discussed in Section IV,B, it should be noted that the systems from which these interpretations were extracted are by no means simple. Qualitative comparisons among the various studies of promoted and unpromoted systems are difficult for the reasons given above, but, in addition, because the variety of forms by which iodine is introduced (e.g., I2, CH3I, or iodide salts) apparently produce different effects (57, 63, 64). Also, many of the systems involve two promoter components (e.g., triphenylphosphine + methyl iodide or tri-p-tolylphosphine + I2X which further complicates the interpretations as to the role(s) of the halide. 

See Footnote t in Section A, p. 166. The bath temperature should be kept below 40°. tThe liquor and the water extract contain the unipositive bis-mer-[N-(2-aminoethyl)-7-methyl-salicylideneiminato]cobalt(III) cation complex, Con,[o-OC6H4C(Me)=N(CH2)2NH2]2 +. To isolate its iodide salt, the aqueous solution is concentrated under vacuum to a volume of 10 mL. After some hours, a solid precipitates. It is collected by filtration, dried by suction, and is then extracted with dichloromethane. The liquor is evaporated to dryness under vacuum, which yields the complex in question (as the monohydrate 3.68 g, 6.8 mmoles, 49%). It can be converted to the desired product ([la)I) by treatment with Na[BH ]/Pd and EtI in alkaline methanol solution under conditions similar to those of the basic procedure. 

To recycle the palladium catalyst used for the Mizoroki-Heckreaction, a reaction using Pd/C as a heterogeneous catalyst was performed in [bmimJIPFe]. Ethyl cin-namate 86 was extracted simply from the ionic liquid using diethyl ether or hexane (Scheme 32). After the reaction, the Pd/C remained suspended in the ionic liquid, suitable for reuse. Since the EtsN+n formed in the course of the Mizoroki-Heck reaction accumulates in the [bmimJfPFe], slightly lower yields were obtained for successive runs. However, washing the ionic liquid with water removed any iodide salt present. 

If bismuth iodide is extracted from an acid solution in the presence of alkali iodide by isobutyl ketone, the organic solvent turns yellow Idn. Limit ly Bi). Platinum and palladium salts interfere. Other interferences can be averted by adding h3q>ophosphorous acid and oxalic acid. 

This reaction is also used on a large scale, to obtain iodine from seaweed. The ash from burnt seaweed ( kelp ) is extracted with water, concentrated, and the salts other than iodides (sulphates and chlorides) crystallise out. The more soluble iodides remain and the liquor is mixed with sulphuric acid and manganese dioxide added the evolved iodine distils off and is condensed. 

On a smaller scale, the largest producer of iodine is Japan where it is extracted from. seaweed containing more than 0.05 parts per million. The most important industrial iodine compound is silver iodide used with silver bromide in photography. Iodine is important in medicine for treating thyroid problems by adding it to table salt. It is used directly as a disinfectant, and a component of d vs. Crystalline silver iodide is used for cloud seeding. 

Carbethoxycyclooctanone (40 g, 0.2 mole) dissolved in 50 ml of dry benzene is added to the stirred sodium hydride over about 30 minutes at room temperature. The mixture is stirred an additional hour at room temperature to complete the formation of the sodium salt. Methyl iodide (284 g, 2.0 mole, a 10-fold excess) is added to the stirred solution over 1 hour and the stirring at room temperature is continued for 20-24 hours. The reaction mixture is poured cautiously into 500 ml of 3 aqueous acetic acid, and the aqueous solution is extracted three times with 100-ml portions of benzene. The combined benzene extracts are washed three times with water and dried over anhydrous magnesium sulfate. Benzene and excess methyl iodide are removed under reduced pressure (rotary evaporator) and the residue is distilled. 

Me3SiCl 14 (40 mmol) is added with stirring to a solution of 20 mmol benTyl benzoate and 40 mmol Nal in 20 mb abs. acetonitrile. The reaction mixture is then heated under reflux for 4 h, cooled to room temperature, and 50 mb H2O is added to saponify the trimethylsilyl benzoate. The reaction mixture is then taken up in 2 X 50 mb ether, which is washed successively with H2O and aqueous thiosulfate solution to remove inorganic salts and iodine. The benzoic acid is then extracted with 2 X 15 mb aqueous 15% NaHC03 solution, leaving benzyl iodide and traces of unreacted benzyl benzoate in the ether layer. On acidification of the aqueous NaHC03 extract 80% benzoic acid is recovered [1] (Scheme 6.17). 

A multiwavelength approach might have been considered as an alternative to chemical derivatisation. Ruddle and Wilson [62] reported UV characterisation of PE extracts of three antioxidants (Topanol OC, Ionox 330 and Binox M), all with identical UV spectra and 7max = 277 nm, after reaction with nickel peroxide in alkaline ethanolic solutions, to induce marked differentiation in different solvents and allow positive identification. Nonionic surfactants of the type R0(CH2CH20) H were determined by UV spectrophotometry after derivatisation with tetrabromophenolphthalein ethyl ester potassium salt [34]. Magill and Becker [63] have described a rapid and sensitive spectrophotometric method to quantitate the peroxides present in the surfactants sorbitan monooleate and monostearate. The method, which relies on the peroxide conversion of iodide to iodine, works also for Polysorbate 60 and other surfactants and is more accurate than a titrimetric assay. 

Most alkaloids are isolated from plant extracts by conversion into the difficultly soluble salts which they form with complex acids such as hexachloroplatinic acid, chlorauric add, phosphotungstic add, hydroferro-cyanic add, Rdnecke s add, etc. Perchloric add, picric add, flavianic add, mercuric chloride, iodine in potassium iodide are also used. 

Mono(bromophenoxy)phenol (I). The mono(bromophenoxy)phenols required for the monomeric models were synthesized by two methods. Method A A mixture of pyridine (90mL), diol (60 mmol), dibromobenzene (56.4g, 240 mmol), anhydrous potassium carbonate (33.3g, 250 mmol) and cuprous iodide (1.62g, 9 mmol) was heated at reflux under nitrogen for 20h. After cooling to room temperature, the reaction mixture was acidified with IN HC1 and the product extracted with chloroform. The chloroform was evaporated and the residue extracted with 10% aq. NaOH. The aqueous phase was acidified, extracted with chloroform, and reduced in volume to an oil that was stirred with 20% aq NaOH to afford the sodium salt of the product. The salt was Isolated and dried to give a white solid. The solid was acidified to pH 1 in water, and the freed mono(bromophenoxy)phenol was washed with water and dried. C-H analysis for products was satisfactory. 

A sample of the sieved particles was also devulcanized by the phenyllithium method (4). An oven-dried 200 mL beverage bottle was charged with 1 g of 18-60 mesh particles and 40 mL of dry benzene. The bottle was capped with a 1-hole cap (extracted neoprene liner) and 10 mL of 2 M phenyllithium added. The mixture was shaken for 6.5 h at room temperature, then 1.5 mL of methanol added. Finally, 4 mL of methyl iodide was injected. At thi point the mixture comprised a rubber solution and a suspension of salts. An aliquot of the solution was taken for gpc analysis. 

Elemental composition Pb 44.94%, 1 55.06%. An accurately weighted amount of the salt may be digested with nitric acid and the acid extract analyzed for lead by AA, ICP or other instrumental techniques. (See Lead.) A few milligrams of salt is dissolved in water and analyzed for iodide anion by ion chromatography. The solutions must be appropriately diluted for these analyses. 

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