Bisulfite spectra

The broad peaks B, D, and E are shifted far upfield by reaction with bisulfite (Eq. 5-11) suggesting that they are not hydrogen bonded and are present in the loop of the stem-loop structure. Peaks A, E, F, and G correspond to resonances 64, 7, 67, and 4, respectively, in (A) and represent fluorouracil in the stem structure. From Chu et al.69i Courtesy of Jack Horowitz. (C) A 31P NMR spectrum of a synthetic 14 base-pair DNA segment related to the E. coli lac operator. The palindromic sequence is TCTGAGCGCTCAGA. The numbers refer to the positions from the 5 end. From Schroeder et al.688... 

Additional results showed that spectra of the condensed lignosulfonate reduced with sodium bisulfite or zinc powder in hydrochloric acid approached the visible spectrum of the uncondensed lignosulfonate, although, in all instances, possessing increased absorption. Oxidizing the reduced lignosulfonate with sodium peroxide destroyed some of the aromatic system. 

The compound m-[Ru(CN)2(bipy)2] 3H20 was first prepared from NaCN, 2,2 -bipyridyl and K2[RuCl5(OH2)] followed by reduction with bisulfite ion. Tt is protonated on the cyanide nitrogen atoms by perchloric acid in acetic acid40 and its IR spectrum has been recorded and discussed.41 An alternative synthesis from reaction of [Ru(C204)(bipy)2] 4H20 with NaCN is available.42... 

Solutions of Sodium and Potassium Sulfite and Bisulfite. Oxygen free, pure sulfite and bisulfite solution containing sodium or potassium ions are stable for more than a year at room temperature. However, at 100°C or above, the sulfate spectrum can be observed already after a few days. Elemental sulfur does not immediately appear. Sometimes, at intermediate and high pH, thiosulfate can be observed in a few experiments. The appearance of these species indicates that they are intermediates in the auto-redox reaction Equations I-III, or that they are formed in a secondary reaction of sulfur (IV) with the product elemental sulfur. The latter reactions are already known. They occur during the degradation of elemental sulfur... 

Work-Up and Isolation of Isomeric Stilbenes Allow the reaction mixture to cool to room temperature, and transfer it to a screw-cap centrifuge tube. Rinse the conical vial with 0.5 mL of dichloromethane, and transfer the rinse to the centrifuge tube. Separate the layers and wash the organic layer sequentially with 1.5 mL of water and then with 2.5 mL of saturated aqueous sodium bisulfite. Finally, wash the organic layer with 1.5-mL portions of water until the pH of the wash is neutral. Transfer the organic solution to a dry centrifuge tube and add several microspatula-tips full of anhydrous sodium sulfate. Occasionally shake the mixture over a period of 10-15 min to facilitate drying add further small portions of anhydrous sodium sulfate if the solution remains cloudy. Consult with your instructor to determine whether you should obtain a " H NMR spectrum of the crude product mixture as in the Miniscale Procedure. 

For the fission process, natural uranium foils and solid U02(N03)2.6H20 were used as targets. The isomer was separated with carrier from irradiated uranium foils in the following manner. The uranium was dissolved in concentrated hydrochloric acid which contained a little concentrated nitric acid. Iodide carrier was added and oxidized to periodate by means of sodium hypochlorite after the solution had been made basic with sodium carbonate. Then the usual redox steps were carried out reduction of 10 to I2 with NH2OH.HCI extraction of I2 into carbon tetrachloride back-extraction Into aqueous sodium bisulfite repetition of l2"I cycles until the y spectrum showed the presence only of iodine products or their xenon decay products. 

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