Silver chlorate

Submitted by D. G. Nicholson and Charles E. Holley, jR.f Checked by George W. WattJ and Job C. Evans J 

Silver chlorate has been found to be an effective oxidizing agent for certain organic compounds. Among these are 

Hitherto, silver chlorate has been prepared by passing chlorine gas into a suspension of silver oxide, sUver carbonate, or an aqueous solution of silver fluoride or by the action of chloric acid on silver oxide, finely divided silver, or silver carbonate. These methods are neither dependable nor satisfactory. 

The procedure outlined below is based upon a considera tion of the solubilities of silver nitrate, silver chlorate, and the corresponding sodium salts. Under appropriate conditions simple metathesis involving interaction of concentrated solutions of silver nitrate and sodium chlorate leads to the desired product. 

A product of sufficient purity for use in the oxidation reactions mentioned above may be prepared by dissolving 170 g. (1 mol) of silver nitrate and 106 g. (1 mol) of sodium chlorate each in 100 ml. of water. After the two solutions are heated to 85°, they are mixed and allowed to cool slowly to 0°, and at this temperature the mother liquor is carefully decanted. Fifty milliliters of distUled water, previously cooled to 0°, is added to the solid product, and the crystals are separated by suction filtration. Yield 150 g. (78.5 per cent). The product contains 95.2 per cent AgClOs as indicated by a silver determination. 

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Ha.la.tes, Silver chlorate, AgClO, silver bromate, AgBrO, and silver iodate, AglO, have been prepared. The halates may decompose explosively if heated. 

Samples of pure CIO2 for measurement of physical properties can be obtained by chlorine reduction of silver chlorate at 90°C ... 

Ethylene glycol combusted spontaneously when it was added to potassium permanganate at ambient temperature and at 100°C in the presence of ammonium or potassium dichromate, sodium chlorite or silver chlorate. With potassium dichromate, the medium reached 170°C. 

MRH values Ammonium bromate 4.52/82, ammonium chlorate 6.36/76, ammonium perchlorate 6.53/70, barium bromate 3.97/76, barium chlorate 4.85/72, calcium bromate 5.02/70, calcium chlorate 6.53/62, potassium bromate 4.56/73, potassium chlorate 5.81/56, potassium perchlorate 6.07/63, silver chlorate 4.60/73, sodium bromate 4.85/70, sodium chlorate 6.90/63, sodium perchlorate 6.69/60... 

Impact sensitivities of mixtures of red phosphorus with various oxidants were determined in a direct drop-ball method, which indicated higher sensitivities than those determined with an indirect striker mechanism. Mixtures with silver chlorate were most sensitive, those with bromates, chlorates and chlorites were extremely sensitive, and mixtures with sodium peroxide and potassium superoxide were more sensitive than those with barium, calcium, magnesium, strontium or zinc peroxides. Mixtures with perchlorates or iodates had sensitivities comparable to those of unmixed explosives, such as lead azide, 3,5-dinitrobenzenediazonium-2-oxide etc. 

Oxidation of Divinylglycol with Silver Chlorate and Osmic Acid... Ill... 

Very little was published on the synthesis of hexitols from unsaturated intermediates between the time of Griner s work and 1933, when it occurred to me that it might be possible to add four hydroxyl groups to divinylglycol by means of a solution of silver chlorate containing a small amount of osmic acid. In carrying out this work I had the assistance of one of my students, Joseph Wiemann. We succeeded far beyond our expectations and obtained allitol, unknown up to that time, and d,l-mannitol. 

Another method of synthesis was also used. This involved the action of chloroacetaldehyde on the Grignard reagent derived from acetylene in order to obtain the meso divinylacetylene dichlorohydrin, CH2CI—CHOH—C=C—CHOH—CH C1, from which one passed to the corresponding hexynetetrol, CH2OH—CHOH—C=C—CHOH— CHjOH. This, in turn, was reduced to the hexenetetrol, CHjOH— CHOH—CH=CH—CHOH—CH2OH, by means of Bourguel s catalyst,8 a dispersion of colloidal palladium on starch. When the hexenetetrol was hydroxylated by the use of silver chlorate and osmic acid, two hexitols, dulcitol and allitol, were obtained. 

An amount of 16 g. of the glycol (m. p. 18°) dissolved in 250 ml. of water was oxidized with 18 g. of silver chlorate and 0.3 g. of osmic acid. The reaction mixture yielded 3 g. of allitol and no D,L-mannitol. We may therefore assign the meso configuration to the divinylglycol melting at 18°, since on hydroxylation it yielded allitol, but not D,L-mannitol. 

Oxidation of Divinylglycol with Silver Chlorate and Osmic Acid. In a typical experiment 100 g. of divinylglycol, 118 g. of silver chlorate and 1 g. of osmic acid were dissolved in 6 liters of water. The reaction mixture was kept at room temperature for several days. It was apparently essential that the reaction be carried out rather slowly. 

Oxidation of l,2,5,6-tetraacetoxyhexene-3 led to the formation of dulcitol tetraacetate. In a typical experiment 22 g. of the tetraacetate was oxidized with 4.4 g. of silver chlorate and 0.1 g. of osmic acid and yielded a sirujj which did not crystallize. The sirup was acetylated again and yielded the corresponding hexitol hexaacetate. The crystals which deposited first were collected and recrystallized from methanol, in which they are difficultly soluble in the cold. The product melted at 166-166.5° and analyzed correctly for a hexitol hexaacetate. Now there was found in the collections of the Ecole Normale Sup rieure an old bottle containing dulcitol hexaacetate, m. p. 167-168°. A mixture of the new and the old hexaacetates was found to melt at 166.5-167.5° the identity of the two compounds was thus beyond doubt. 

CHOAc—CHOAo—CHOH—CH2OH, by the action of silver chlorate and osmic acid. 

Hydrogenation of the pentenynol with Bourguel s catalyst5 gives the corresponding divinylcarbinol, CH2=CH—CHOH—CH=CH2, b. p. 114.5-116°, dig 0.8648, mdw 1.4452. Treatment of this divinylcarbinol with the theoretical quantity of silver chlorate and a little osmic acid yielded a sirup which has not crystallized. From the acetylation of this sirup there was obtained a small quantity of D,L-arabitol pentaacetate and a viscous liquid which has not been studied further but certainly contains one or both of the other pentitol pentaacetates. 

Aluminium chlorate, 0065 Barium chlorate, 0205 Cadmium chlorate, 3952 Chloric acid, 3996 Lead(II) chlorate, 4105 Magnesium chlorate, 4083 Manganese(II) chlorate, 4087 Potassium chlorate, 4017 Silver chlorate, 0011 Sodium chlorate, 4039 Zinc chlorate, 4106 See Other METAL HALOGENATES... 

Silver bromate, 0007 Silver buten-3-ynide, 1408 Silver chlorate, 0011 Silver chloride, 0008 Silver chlorite, 0010... 

In turn, vinylacetic acid served17 for the synthesis of DL-erythrono-1,4-lactone (12). The starting compound was first hydroxylated by means of the barium chlorate-osmium tetraoxide reagent to 3-hydroxybutanolactone, dehydration of which with phosphorus pen-taoxide yielded isocrotonolactone, readily convertible with silver chlorate into 12. 

Silver chlorate forms the triammine, [Ag(NH3)3]C103 silver carbonate the tetramminc, [Ag(NH3)2]2CO 3 and silver oxide itself forms diammino-silver oxide, Ag20.2NH3> and the hydroxide, [Ag(NIi3)2]OII.5 Diammino-silver hydroxide appears to be more strongly dissociated than barium hydroxide.6... 

Silver chlorate [7783-92-8] M 191.3. Recrystd three times from water (lOml/g at 15° 2ml/g at 80°). 

Silver chlorate is a strong oxidg agent and forms powerful expl mixts with combustible materials. According to A.Wachter(See in Ref 2), silver chlorate alone can decomp explosively when heated very rapidly... 

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