Disodium disulfite

Methoxy-3-phenylpropyl Tellurium Trichloride1 2.0 g (12.5 mmol) tellurium dioxide are dissolved in 10 m/ concentrated hydrochloric acid and 40 ml methanol are added. 1.75 g (14.8 mmol) of allylbenzene are added. The mixture is refluxed for 24 h and then cooled to 20°. This solution containing the 2-methoxy-3-phenylpropyl tellurium trichloride was reduced with aqueous disodium disulfite to the ditellurium compound. 

Bis[acylmethyl] tellurium dichlorides and aryl benzoylmethyl tellurium dichlorides lose the acylmethyl group under conditions generally used for the reduction of diorganyl tellurium dichlorides. However, these acylmethyl tellurium dichlorides were successfully reduced in a two-phase system consisting of dichloromethane and an aqueous solution of disodium disulfite. The acylmethyl tellurium compounds escape into the organic phase and are protected from further attack by the reducing agent1. 

Bisfbenzoylmethyl] Tellurium A solution of 1.09 g (2.3 mmol) of bis[benzoylmethyl] tellurium dichloride in 100 m/ dichloromethane is shaken vigorously in a separatory funnel for 15 min with a solution of 0.50 g (2.6 mmol) disodium disulfite in 50 ml water. The yellow organic phase is separated, washed once with water, and then dried for 10 min with anhydrous calcium chloride. The mixture is filtered and the filtrate evaporated. The residue is recrystallized from petroleum ether (40-60°) yield 53% m.p. 79°. 

Bis[trichlorotelluro]biphenyl1 and l,4-bis[trichlorotelluro]benzene2 were reduced by aqueous disodium disulfite to polymeric ditelluriums. 

Benzolellurazoles can be halogenated with elemental chlorine or bromine to give the Te,Te-dihalides. These dihalides are reduced by aqueous disodium disulfite to 1,3-benzotellurazoles3. 

SYNS DISODIUM DISULFITE DISODIUM PYROSULFITE DISULFUROUS ACID, DISODIUM SALT SODIUM DISULFITE SODIUM METABISULFITE SODIUM METABISULPHITE SODIUM PYROSULFITE... 

Generally, the reduction of aryl tellurium trihalides by a variety of reducing agents leads to diaryl ditellurium compounds. However, the reduction of aryl tellurium trihalides with stabilizing groups in the or//to-position to the tellurium atom, by sodium hydrogen sulfite, disodium disulfite, or hydrazine hydrate " to aryl tellurium halides shows that the reduction can be stopped at the tellurium halide stage. 

Bis[2-methoxy-3-phenylpropyl] Ditellurium 2.0 g tellurium dioxide (12.5 mmol) are dissolved in 10/n/ concentrated hydrochloric acid. The yellow solution is diluted with 40 m/ methanol. 1.75 mg (14.8 mmol) allylbenzene are addded, the mixture is refluxed for 24 h, and then cooled to 20°. The yellowish homogeneous solution is poured into a separatory funnel containing 5g disodium disulfite in 100 m/ water and 100 m/ dichloromethane. The mixture is shaken, the red dichloromethane phase separated, dried, and evaporated. The red, oily residue is flash chromatographed on silica gel with dichloromethane as the mobile phase yield 80%. 

When 1-dodecene, tellurium dioxide in coneentrated hydroehloric acid, and ethanol or isopropanol were reacted and the products reduced with disodium disulfite, bis[2-hydroxydodecyl] ditellurium (m.p. 64°) was isolated in 21 % yield (R OH = ethanol) or 29% yield (R = /-C3H7OH) in addition to the corresponding bis[2-alkoxydodecyl] ditelluriums. Bis[2-tetrahydrofurylmethyl ditellurium (62% yield) and his[henzo-2-dihydrqfurylmethy[ ditellurium (83% yield) were similarly prepared . ... 

The additions of tellurium tetrahalides to olefins in the presence of alcohols proceed equally well when the tetrahalides are generated in the reaction mixture from tellurium dioxide and chlorotrimethylsilane in methanoP or concentrated hydrochloric acid/methanol. trans-2-Methoxycyclohexyl tellurium trichloride was obtained in this manner in quantitative yield . In the reactions of terminal alkenes, the TeCl3 group (from TeO and concentrated hydrochloric acid) added according to the Markovnikov rule producing 2-alkoxy-1 -alkyl tellurium trichlorides. The trichlorides were not isolated but were reduced with disodium disulfite to the ditellurium compounds, which, in turn, were converted to the tellurium trichlorides by treatment with sulfuryl chlorides. For data on these tellurium trichlorides see p. 316. The overall yields range from 15 to 70%. 

Nitrophenyl tellurium tribromide and 2-benzeneazophenyl tellurium trichloride were reduced to the aryl tellurium halide by sodium hydrogen sulfite , disodium disulfite, or hydrazine hydrate . 

Disodium disulfite disodium pyrosulfite disulfurous acid, disodium salt E223 natrii disulfis sodium acid sulfite sodium pyrosulfite. 

Disodium disulfite. See Sodium metabisulfite Disodium dithionate Disodium dithionite. See Sodium hydrosulfite... 

Sodium merthiolate. See Thimerosal Sodium metaarsenate. See Sodium arsenate Sodium metaarsenite. See Sodium arsenite Sodium metabisulfite CAS 7681-57-4 EINECS/ELINCS 231-673-0 UN NA 2693 (DOT) INS223 E223 Synonyms Disodium disulfite Disodium pyrosulfite Disulfurous acid disodium salt Pyrosulfurous acid disodium salt Sodium bisulfite... 

Trade Names EutexCBS Disodium disulfite. See Sodium metabisuKHe Disodium dKhionate Disodium dithionite. See Sodium hydrosuKHe Disodium 3,3 -(dodecylimino) dipropionate. See Disodium lauriminodipropi-... 

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