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Sodium bisulfite additions

Mandelic acid is best prepared by the hydrolysis of mandeloni-trile with hydrochloric acid. The mandelonitrile has been prepared from amygdalin, by the action of hydrocyanic acid on benzaldehyde, and by the action of sodium or potassium cyanide on the sodium bisulfite addition product of benzaldehyde. ... [Pg.62]

The method in the procedure differs from any previously described in that the sodium bisulfite addition product of benzal-dehyde is prepared in the presence of sodium cyanide and the nitrile is formed immediately. [Pg.62]

Muconic acid has been obtained in a variety of ways. The procedures that seem most important from a preparative point of view are by treatment of ethyl o ,5-dibromoadipate with alcoholic potassium hydroxide, by condensation of glyoxal (as the sodium bisulfite addition product) with malonic acid, by heating ethyl l-acetoxy-l,4-dihydromuconate (obtained by condensing ethyl oxalate and ethyl crotonate, acetylating, and reducing),and by oxidation of phenol with peracetic acid. ... [Pg.60]

The crude ester is cooled, an equal volume of benzene is added, then the free acid is neutralized by shaking with about 250 cc. of a 10 per cent solution of sodium carbonate (Note 4). The benzene solution is poured into 1300 cc. of a saturated solution of sodium bisulfite (about 60 g. of technical sodium bisulfite per 100 cc.), contained in a wide-neck bottle equipped with an efficient stirrer, and the mixture stirred for two and a half hours. The mixture soon warms up a little and becomes semi-solid. It is filtered through a 20-cm. Buchner funnel and carefully washed, first with 200 cc. of a saturated solution of sodium bisulfite, finally with two 150-cc. portions of benzene (Notes 5 and 6). The white pearly flakes of the sodium bisulfite addition product are transferred to a 3-I. round-bottom wide-neck flask equipped with a mechanical stirrer and containing 700 cc. of water, 175 cc. of concentrated sulfuric acid, and 500 cc. of benzene. The flask is heated on a steam bath under a hood, the temperature being kept at 55°, and the mixture is stirred for thirty minutes (Note 7). The solution is then poured into a separatory funnel, the benzene separated and the water layer extracted with a 200-cc. portion of benzene. The combined benzene solution is shaken with excess of 10 per cent sodium carbonate solution to remove free acid and sulfur dioxide (Note 8). The benzene is washed with a little water and then dried over anhydrous potassium carbonate (Note 9). The benzene is distilled at ordinary pressure over a free flame from a 500-cc. Claisen flask, the solution being added from a separatory funnel as fast as the benzene distils. It is advisable to distil the ester under reduced pressure although it can be done under ordinary pressure. The fraction distilling around n8°/5mm., 130710 mm., 138715 mm., 148725 mm., 155735 mm., or... [Pg.70]

A solution of 10 g (0.06 mol) of ethyl thiolbenzoate in 200 ml of 70% ethanol is refluxed for 6 hours with 50 g of Raney nickel. After the removal of the catalyst the filtrate is distilled and the aldehyde is isolated from the distillate by treatment with a saturated (40%) solution of sodium bisulfite. The yield of benzaldehyde-sodium bisulfite addition complex is 8.0 g (62%). [Pg.205]

Dihydroxyindoles also form complexes readily with sodium bisulfite,118,123, 156 and the presence of the 5,6-dihydroxy -A-methyl-indole-sodium bisulfite addition complex among the products obtained... [Pg.251]

F. Sodium Bisulfite Addition Product Formation The red color of aminochrome solutions is rapidly discharged by the addition of sodium bisulfite with the formation of pale-yellow fluorescent solutions. The reactions of adrenochrome with sulfites and bisulfites have been the subject of several previous reports.12, 102.109.118,119.123,128,148.182.155. 158,173-177 Although it was originally... [Pg.263]

The 7-iodoaminochromes also form addition products with sodium bisulfite, although formation of these adducts usually appears to be accompanied by some deiodination, with the consequent formation of the corresponding deiodinated complexes.155 The 7-iodonor-adrenochrome-sodium bisulfite addition product has been reported to be more stable in this respect (i.e. it shows less tendency to deiodinate) than the corresponding 7-iodoadrenochrome adduct.119 Although it has not proved possible to demonstrate effectively the presence of both the 7-iodoaminochrome complex and the corres-... [Pg.264]

Paper Chromatographic Data on Some Aminochrome-Sodium Bisulfite Addition Products"... [Pg.265]

The sodium bisulfite addition compounds must have a free (or potentially free) ketone-type carbonyl group, since they readily form derivatives with typical ketone reagents such as semicarbazide and 2,4-dinitrophenylhydrazine.174 Decomposition of these derivatives with alkali gives the corresponding adrenochrome derivatives e.g., adrenochrome monosemicarbazone would be obtained from the semicarbazone of the adrenochrome-sodium bisulfite complex.174 If one accepts Tse and Oesterling s formulation of the adrenochrome-sodium bisulfite complex, the semicarbazone would probably have a basically similar structure (i.e. 82). This type of structure is more... [Pg.267]

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... [Pg.282]

A sensitive spectrophotometric method based on the strong absorption of the aminochrome-sodium bisulfite addition products (see Section IV, F) at ca. 350 m/x. has been described recently by van Espen128and Oesterling and Tse 277-278 for determining total catecholamines. While not as sensitive as the fluorimetric procedures, this method is considerably more sensitive than the older colorimetric methods based on the visible absorption peak of the aminochromes. Also, it does not have many of the disadvantages (e.g. costly equipment and unstable blanks) often associated with fluorimetric techniques. The basic procedure can be satisfactorily applied to the differential determination of mixtures of adrenaline, noradrenaline, dopamine, metanephrine, and normetanephrine.178... [Pg.283]

This treatment removes ethyl (l-ethylpropylidene)-cyano-acetate as a water-soluble sodium bisulfite addition product (p. 46). [Pg.45]

Extraction of the aqueous solution removes ethyl cyanoacetate from the aqueous solution of the sodium bisulfite addition product of ethyl (l-ethylpropylidene)-cyanoacetate. [Pg.47]

Acetone cyanohydrin has been prepared from acetone and anhydrous hydrogen cyanide in the presence of a basic catalyst such as potassium carbonate, potassium hydroxide, or potassium cyanide 1 by the reaction of potassium cyanide on the sodium bisulfite addition product of acetone 2 and by the action of hydrogen cyanide, prepared directly in the reaction mixture, on an aqueous solution of acetone.3... [Pg.2]

Assay Mix 50.0 mL of sample with 500 mg of tartaric acid, shake for 5 min, and filter. Dry the filtered oil over anhydrous sodium sulfate, and then pipet 10.0 mL of the clear, treated oil into a 150-mL cassia flask. Add 75 mL of a 30% solution of sodium bisulfite, stopper the flask, and shake until a semisolid to solid sodium bisulfite addition product has formed. Allow the mixture to stand at room temperature for 5 min, then loosen the stopper, and immerse the flask in a water bath heated to between 85° and 90°. Maintain the water bath at this temperature, shaking the flask occasionally, until the addition product dissolves, and then continue heating and intermittently shaking for another 30 min. When the liquids have separated completely, add enough 30% sodium bisulfite solution to raise the lower level of the oily layer within the graduated portion of the flask s neck. Calculate the percentage, by volume, of the citral by the formula... [Pg.250]

Add 75 mL of a 30% solution of sodium bisulfite, stopper the flask, and shake until a semisolid to solid sodium bisulfite addition product has formed. Allow the mixture to stand at room temperature for 5 min, then loosen the stopper, and immerse the flask in a water bath heated to between 85° and 90°. Maintain the water bath at this temperature, shaking the flask occasionally,... [Pg.32]

Condensation of sodium salts of acinitroalkanes with the sodium bisulfite addition products of aldehydes in the presence of trace of alkali or weak acid also gives nitro alcohols as reported byKamlet o. [Pg.122]

The yields of nitro alcohols from simple nitroparaffins and aliphatic aldehydes or benzaldehyde are usually above 60%. The condensations are generally carried out with aqueous ethanolic sodium hydroxide, although weaker bases are sometimes desirable to prevent polymerization of the aldehyde. Sodium bisulfite addition compounds of the aldehydes are sometimes used. Better results are obtained with sodium methoxide than with alkali hydroxides in the condensation of nitroethane with formaldehyde. Sodium alkoxides are also used to effect the condensation of nitroethane with acetone and cyclohexanone. Condensation proceeds to the nitroalkanediol stage in certain cases with both nitromethane and with formaldehyde. ... [Pg.93]

The sodium bisulfite addition products of aldehydes have been converted by the action of potassium cyanide and an amine to a-alkylamino cyanides. The procedure is best suited for obtaining amino nitriles derived from formaldehyde and simple amines and is illustrated in the preparation of diethylaminoacetonitrile (90%). ... [Pg.308]

Bearrangemente might alao be expected but ee n to have Uw, BeMom obeerved The isolation of the sodium bisulfite addition compound of piopkmaldehyde firom the reaction of trimethylene oxich-with eodium bisulfite, however, provides an example. It is intereaUn CH.-CH ... [Pg.183]

Solution No. Povidone K 12 Povidone K 17 pH (adjusted) Sodium bisulfite addition... [Pg.36]

Preparation, (a) By addition of 40% sulfuric acid to an aqueous solution of acetone and sodium cyanide at 10-20°. (b) Reaction of potassium cyanide with the sodium bisulfite addition compound of acetone gives material which is less pure but satisfactory for immediate use. ... [Pg.736]

Aldehydes. Conversion to solid sodium bisulfite addition product with excess reagent, removal of nonaldehydic material by washing with alcohol or ether, and regeneration usually with acid, base, or sodium carbonate, provides a convenient method of purification. Examples syringic aldehyde, n-hexaldehyde. ... [Pg.1257]

Henry reaction. Formation of nitroalcohols by an aldol-type condensation of nitroparaffins with aldehydes in the presence of base (Henry) or by the condensation of sodium salts of aci nitroparaffi ns with the sodium bisulfite addition products of aldehydes in the presence of a trace of alkali or weak acid (Kamlet). Widely used in sugar chemistry. [Pg.638]

Hinsberg oxindolc synthesis. Formation of oxindoles from secondary aryl amines and sodium bisulfite addition compound of glyoxal primary aryl amines give glycine or glycinamide derivatives. [Pg.652]

Air Drawing of air through impinger filled with 1% sodium bisulfite addition of CTA, concentrated sulfuric acid equilibration for 1 hour. Absorbance at 580 nm No data 98.7 4.7 Petreas et al. 1986... [Pg.344]

Crude bromophenanthrene prepared by the bromination of technical (90%) phenanthrene and purified by distillation only was used by the submitters in this preparation. The an-thracene-9-aldehyde, which may be formed from the anthracene present as an impurity in 90% phenanthrene, does not form a sodium bisulfite addition product and so will not contaminate the phenanthrene-9-aldehyde. The checkers used 9-bromophe-nanthrene, m.p. 54-56° (p. 20), exclusively, but without any advantage in yield. The submitters report yields of 55-60% from pure 9-bromophenanthrene. [Pg.44]


See other pages where Sodium bisulfite additions is mentioned: [Pg.94]    [Pg.473]    [Pg.139]    [Pg.205]    [Pg.234]    [Pg.251]    [Pg.252]    [Pg.260]    [Pg.264]    [Pg.266]    [Pg.266]    [Pg.267]    [Pg.267]    [Pg.283]    [Pg.36]    [Pg.54]    [Pg.473]    [Pg.343]    [Pg.604]   
See also in sourсe #XX -- [ Pg.8 , Pg.68 ]

See also in sourсe #XX -- [ Pg.8 , Pg.68 ]




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