Bisulfite aqueous chemistry

Strike sees a point to this in Vogel s text Practical Organic Chemistry (3 ed.)[37]. In it, Vogel crystallizes his ketones using a saturated sodium bisulfite solution that a/so contains a little solvent. This is in contrast to the straight up aqueous (only water) solution that Strike described above. Here is A/hat Vogel said on page 342 ... 

Either pure aqueous or aqueous/solvent solutions work. It is entirely up to the preference of the chemist as to which one they use. Just to make one feel more secure, there is a little test one can do with the bisulfite solution to see if they got it right. Just put a little of that ketone known as acetone into the saturated solution and watch the crystals grow. Isn t it nice how chemistry works ... 

The absorption of sulfur dioxide in alkaline (even weakly alkaline) aqueous solutions affords sulfites, bisulfites, and metabisulfites. The chemistry of the interaction of sulfur dioxide with alkaline substances, either in solution, slurry, or soHd form, is also of great technological importance in connection with air pollution control and sulfur recovery (25,227,235—241). Even weak bases such as 2inc oxide absorb sulfur dioxide. A slurry of 2inc oxide in a smelter can be used to remove sulfur dioxide and the resultant product can be recycled to the roaster (242). 

An important reaction in the chemistry of naphthalenes is the Bucherer reaction,i.e. the conversion of naphthols 1 to naphthylamines 2 as well as the reverse reaction. The reaction is carried out in aqueous medium in the presence of catalytic amounts of a sulfite or bisulfite. Apart from very few exceptions it does not apply to benzene derivatives, which limits the scope of that reaction. 

Assay procedures for dopamine which are superficially similar to the lutin procedure described above have been reported recently.266-268 The chemistry of the production of the fluorophore from dopamine is, however, somewhat different since the fluorophore is not a 5,6-dihydroxyindoxyl, it is incorrect to refer to the trihy-droxyindole fluorophore of dopamine (cf. ref. 252). Oxidation of the extracted catecholamine is usually carried out with iodine,266-268 presumably with the formation of 7-iodonorepinochrome. The aminochrome is subsequently rearranged to 5,6-dihydroxyindole (it is probable that deiodination accompanies the rearrangement in this case) by a solution of sodium sulfite in aqueous alkali the solution is acidified before measuring the fluorescence of the product (which is said to form relatively slowly and to be very stable).266-268 Irradiation of the reaction mixture with ultraviolet light accelerates the maximal development of fluorescence.266 Since acidification will produce sodium bisulfite in the reaction mixture, it is probable that the fluorophore is a 5,6-dihydroxyindole-sodium bisulfite addition complex. Complexes of this type are known to be both fluorescent and relatively stable in dilute acid solution.118 123,156 265 They also form relatively slowly.255... 

The autoxidation of aqueous solutions of sulfur dioxide (sulfite, bisulfite) is a classic problem in chemistry. Basic features of this reaction have been known since early in this century, when it was established that the reaction is trace metal ion catalyzed (1 ) and most likely involves free radicals (2). Certain chemical effects associated with sulfite autoxidation were noted also. Before the turn of the century, it was noted that sulfite would induce the oxidation of transition metal ions (3) and it was reported later that the oxidation of organic compounds was brought about during sulfite autoxidation ( 0. Conversly, organic compounds were also shown to serve as inhibitors of sulfite autoxidation (5). 

When dissolved into the aqueous phase, the atmospheric constituents alter the chemistry of the aqueous layer through various chemical or electrochemical reactions. One important chemical process is the deposition of sulfur dioxide into the aqueous layer to form bisulfite (HS03 ) ions ... 

The aqueous sulfite/bisulfite solution is reacted with the glycidyl ethers to produce the final sulfonated product. As seen in Figure 8.4, the epoxide group as well as any chlorine atoms on the higher oligomers are sulfonated. For each mole of sodium sulfite that is reacted, an equimolar amount of sodium chloride is produced. Looking at the chemistry, it is easy to surmise that the chloro-glyceryl ethers from step 1 (Section 8.2) could have been used in this reaction with only sodium sulfite, but an excess of the undesired salt by-product would have been formed. 

One of the interesting outcomes of this chemistry are the esters of sulfosuccinic acid. Jaeger prepared them as follows maleic anhydride was first treated with two moles of alcohol (see Sec. 3.4.3) to form the diester. On treating the dialkyl maleate with aqueous sodium bisulfite, sodium dialkyl-sulfosuccinate 51 was obtained. 

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