Sodium thiosulfate, preparation

Mechlorethamine Cold packs Sodium thiosulfate Prepare 1/6 M solution by adding 4 mL of 10% solution to 6 mL sterile water inject 2 mL for each mg of mechlorethamine. Follow with 1 mL SQ (0.1 mL doses clockwise around area) may repeat every 3-4 hours if needed. Sodium thiosulfate must be diluted prior to administration. 

Two hundred milliliters (2.4 mols) of 12 N hydrochloric acid is placed in a 500-ml. three-necked round-bottomed flask fitted with a dropping funnel containing 50 ml. (approximately 0.2 mol) of saturated aqueous sodium thiosulfate (prepared and used at room temperature), an all-... 

Thiosulfuric Acid. Thiosulfuiic acid [14921 -76-7] is relatively unstable and thus cannot be recovered from aqueous solutions. In laboratory preparation, a lead thiosulfate [26265-65-6] solution is treated with H2S to precipitate PbS, or a concentrated solution of sodium thiosulfate [7772-98-7] is treated with HCl and cooled to — 10°C to crystalline NaCl. Aqueous solutions of thiosulfuric acid spontaneously decompose to yield sulfur, SO2, and polythionic acids, H2S O. Thiosulfuric acid is a strong acid comparable to sulfuric acid. Dissociation constants, = 0.25, = 0.018, have been... 

Calcium thiosulfate has been prepared from calcium sulfite and sulfur at 30—40°C, or from boiling lime and sulfur in the presence of sulfur dioxide until a colorless solution is obtained. Alternatively, a concentrated solution of sodium thiosulfate is treated with calcium chloride the crystalline sodium chloride is removed at low temperature. Concentrated solutions of calcium thiosulfate are prepared from ammonium thiosulfate and lime the Hberated ammonium ion is recycled to the ammonium thiosulfate process (85). 

Gold thiosulfate complexes of the form Na2[Au(S202)2] 2H20 [19153-98-1] are prepared by addition of gold trichloride to concentrated sodium thiosulfate solution (89). The gold is completely reduced and some thiosulfate is oxidized to tetrathionate. This complex has been used in the treatment of rheumatoid arthritis. 

Organic thiosulfate salts are usually prepared by the reaction of alkyl chlorides with sodium thiosulfate ... 

Isothiazole itself is best prepared by the reaction between propynal, ammonia and sodium thiosulfate (see Section 4.17.9.3). A wide range of substituted mononuclear isothiazoles can be obtained by oxidative cyclization of y-iminothiols and related compounds (see Section 4.17.9.1.1). Substituents at the 3-position need to be in place before cyclization, but 4-substituents are readily introduced by electrophilic reagents (see Section 4.17.6.3), and 5-substituents via lithiation (see Section 4.17.6.4). 

The recovered dg-dimethyl sulfoxide may be recycled to prepare additional deuteriomethyl iodide or purified for use as a reagent by gentle warming with a little solid sodium thiosulfate followed by distillation from barium oxide. Both products show 99% deuteration. ... 

Preparation of 3 5-diiodo-4-(4 -hydroxyphenoxy)phenylacetic acid (diac) A solution of ethyl 3 5-diiodo-4-(4 -methoxyphenoxy)phenyl acetate (9.5 g) in acetic acid (60 ml) was heated under reflux with hydriodic acid (SG 1.7, 50 ml) and red phosphorus (0.5 g) for 1 hour. The hot solution was filtered and the filtrate concentrated at 50°C and 15 mm of mercury to above 20 ml. The residue was treated with water (70 ml) containing a little sodium thiosulfate to decolorize the product. The solid was collected by filtration and purified by the method of Harington and Pitt-Rivers [Biochem. J. (1952), Vol. 50, page 438]. Yield 8,36 g (95%). After crystallization from 70% (v/v) acetic acid it melted at 219°C. 

The decolonization of the yellow product (Note 11) is achieved by dissolving the product in an equal volume of carbon tetrachloride (ca. 12 ml.) and vigorously shaking the solution thus obtained with 1.5 ml. of a freshly prepared aqueous 35% sodium thiosulfate. The two layers are completely separated after 5 minutes. The colorless bottom layer is drawn off into a 50-ml. Erlenmeyer flask. The top layer is extracted three times with 1.5 ml. of carbon tetrachloride. The combined carbon tetrachloride solution is dried over 0.5 g. (Note 12) of anhydrous magnesium sulfate for 30 minutes. The solution is then filtered into a 50-ml. distilling flask, and the magnesium sulfate is washed several times with carbon tetrachloride (total 5 ml.). The solvent is removed, and the colorless product is distilled as described above, affording 14.7-15.8 g. (69-74% overall, based on hexanoic acid 88-92% for the decolonization step) of colorless 2-bromohexanoyl chloride, b.p. 45-47° (1.5 mm.), n22 d 1.4706 (Note 13), i 4 1.4017 (Notes 14 and 15). 

Each entry must be dated. This not only makes it easier to retrieve information in the future, but it makes it possible to reconstruct the chronology of work performed and correlate it with other activities. In an analytical laboratory where a customer alleged that a sodium thiosulfate reagent solution used in a titration had been improperly prepared, the date reference made it possible one year later to tie the sample in question to a specific batch of reagent. This careful record prevented a threatened lawsuit. 

N Sodium thiosulfate solution is prepared daily by dilution of stock solution of known concentration. 

Available from K K Laboratories or may be prepared in 89% yield by the following procedure. To a solution of 393 g. (2.63 moles) of sodium iodide in 1 1. of reagent grade acetone is added 394 g. (2.50 moles) of l-bromo-3 chloropropane (Aldrich Chemical Co.). After stirring 2 hours at room temperature, the mixture is filtered, the sodium bromide is washed with acetone, and the acetone is evaporated at reduced pressure. A dark iodine color is present along with some solid sodium salts. The oil is dissolved in ether, and the solution is washed with a 10% aqueous sodium thiosulfate solution. The ethereal layer is separated, dried over anhydrous sodium sulfate, and evaporated at reduced pressure to yield 454 g. of an oil that can be used without further purification. 

Many high explosives can be synthesized from the reaction of picryl chloride with various nucleophiles. 2,2, 4,4, 6,6 -Hexanitrodiphenylsulfide (10) can be prepared from the reaction of picryl chloride (87) with sodium thiosulfate in ethanol solution in the presence of magnesium carbonate. Oxidation of (10) with fuming nitric acid forms 2,2, 4,4, 6,6 -hexanitrodiphenylsulfone (88). ... 

The Cd/CdS electrode was also prepared in solutions containing cadmium sulfate and sodium thiosulfate using the potentiodynamic method [183]. The electrochemical behavior of such electrodes in electrolytes containing sulfide ions was studied. 

Two methods for the preparation of [l,2,3]triazolo[4,5-, pyridazine-4-thione 29 were reported by Bussolari et al. involving nucleophilic substitution of sulfur by displacement of the 4-chloro substituent from 28 and of the oxygen atom of 4-lactam derivative 30 using sodium thiosulfate and phosphorus pentasulfide, respectively (Scheme 18) <1996BMC1725>. 

The workers who reported the chemistry described in Scheme 85, also reported a new preparation of this 8-thiapurine ring system via reaction of 6-amino-5-nitrosopyrimidine with sodium thiosulfate in acidic media (Scheme 86), and extended this methodology to the synthesis of 4-/3-D-ribofuranosyl[l,2,5]thiadiazolo[3,4-r/]pyrimi-dines <2007H(72)573>. The latter article includes the facile synthesis of these compounds, as well as the evaluation of antitumor and antiviral activity. 

The approach to pyrazino[2,3-, ]quinoxalines shown in Equation (114) has now been used to prepare pyrazino[2,3-, ]pyrazines <2007EJ01237>, whose nickel complexes have also been prepared. The same publication also describes the formation of 172 by treatment of conjugated system 173 with sodium thiosulfate. The former is reconverted to the latter on exposure to air and, on further aerial oxidation at 130 °C, 173 eventually forms the highly condensed system 174. Detailed studies of the formation of the tetrahydropyrazinopyrazine 101 have been reported, along with theoretical studies, and structural data for the trans isomer <2007T6915>. 

The combined filtrates may be titrated with 1 N sodium thiosulfate solution to determine the yield of monochlorourea. This preparation of monochlorourea is a modification of procedures previously described> ... 

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