Sodium sulfate, spectra

In a 250 ml Erlenmeyer flask covered with aluminum foil, 14.3 g (0.0381 mole) of 17a-acetoxy-3j5-hydroxypregn-5-en-20-one is mixed with 50 ml of tetra-hydrofuran, 7 ml ca. 0.076 mole) of dihydropyran, and 0.15 g of p-toluene-sulfonic acid monohydrate. The mixture is warmed to 40 + 5° where upon the steroid dissolves rapidly. The mixture is kept for 45 min and 1 ml of tetra-methylguanidine is added to neutralize the catalyst. Water (100 ml) is added and the organic solvent is removed using a rotary vacuum evaporator. The solid is taken up in ether, the solution is washed with water and saturated salt solution, dried over sodium sulfate, and then treated with Darco and filtered. Removal of the solvent followed by drying at 0.2 mm for 1 hr affords 18.4 g (theory is 17.5 g) of solid having an odor of dihydropyran. The infrared spectrum contains no hydroxyl bands and the crude material is not further purified. This compound has not been described in the literature. 

P-Hydroxy-A-norpregn-3(5)-en-2-one (7) A solution of the hydroxy-methylene steroid (5) (24.8 g) dissolved in 240 ml of acetic acid and 240 ml of ethyl acetate is ozonized at — 10° with one molar equivalent of ozone. The resulting solution is diluted with 240 ml. of water and 60 ml of 30 % hydrogen peroxide and allowed to stand overnight. The solution is diluted with 1.5 liters of water and extracted with 3 x 700 ml portions of ethyl acetate. The combined extracts are washed with water, saturated sodium chloride solution, dried over sodium sulfate and concentrated to dryness under vacuum, leaving 23.4 g of a colorless amorphous residue of crude diacid. This material shows a maximum in the ultraviolet spectrum at 224 mp (s 6,400) indicating a 53 % yield of unsaturated acid (6). It is used without further purification. 

Extracts of these fat samples were treated with sodium sulfate-concentrated sulfuric acid mixture and fuming acid by the method described by Schechter et al. 5) in order to separate the organic-chlorine compound from the fatty materials. An infrared spectrum from 7 to 15 microns on carbon disulfide solutions of the residues from the fat qualitatively identified the organic-chlorine compound as toxaphene. All the bands of toxaphene in this spectral region were plainly seen in the treated steer extract, whereas none of the absorption bands were visible in the untreated steer extract. 

Test 2 Examine by infrared absorption spectrophotometry, according to the general procedure (2.2.24), comparing with spectrum obtained with primaquine diphosphate Chemical Reference Substance (CRS). Examine the substance as discs prepared as follows dissolve separately 0.1 g of primaquine diphosphate and the reference substance in 5 mL of water R, add 2 mL of dilute ammonia R and 5 mL of chloroform R and shake dry the chloroform layer over 0.5 g of anhydrous sodium sulfate R prepare a blank disc using about 0.3 g of potassium bromide R, apply dropwise to the disc 0.1 mL of the chloroform layer, allowing the chloroform to evaporate between applications dry the disc at 50 °C for 2 min. 

Preparation of 17-cyclopropylmethyl-14-hydroxynorcodeinone. A solution of 17-cyclopropylmethylnorcodeinone (0.20 g, 0.59 mmol), formic acid (90%, 0.304 g), water (0.504 g), EtOAc (0.27 g), and hydrogen peroxide (30%, 0.17 g) was heated at 42°-43°C for 15 hr, added water (20 ml), basified with Na2C03 (1.02g), and extracted with EtOAc (80 ml and 2 times 20 ml). The combined extract was washed with water, dried over anhydrous sodium sulfate, and evaporated in vacuo to dryness to give 17-cyclopropylmethyl-14-hydroxynorcodeinone (0.10 g, 56% yield). The Rf value in TLC and the IR spectrum of the product were comparable to those obtained from an authentic sample. 

The mixture was next quenched with water and the resulting precipitated oil taken up in pentane, dried with sodium sulfate, and distilled under vacuum. The product was collected at 100° to 110°C at 0.001 mm/Hg, nD24-5 1.50 60. The infrared and ultraviolet spectrum corresponded to 10,ll-didehydro-9-ethoxy-9,12-dihydroretinol acetate, using carotenoid nomenclature based on the parent compound retinol. 

Pronounced shifts of cyclopeptide signals in the XH NMR spectrum caused by adding sodium sulfate to a solution of 28 in D2O/CD3OD 1 1 (v/v) clearly indicated that the anion is bound inside the cage. Force-field calculations provided a picture of the structure of the complex formed, which is stabilized by a well-defined array of hydrogen bonds (Fig. 4). 

Conformational analysis of BS I by c.d. spectroscopy indicated that the protein contained 30-40% of /3 structure in its native conformation.623 The c.d. spectrum was relatively insensitive to alteration in pH, removal of bound metal, and addition of methyl a-D-galactopyranoside. However, addition of dodecyl sodium sulfate or 2,2,2-trifluoroethanol resulted in the formation of some a-helical structure, and was accompanied by the loss of polysaccharide-precipitating capacity. Urea (8 M) irreversibly denatured the lectin. 

The ether layer is washed successively with 5% hydrochloric acid, 5% sodium carbonate aqueous solution and water, and then dried over sodium sulfate. Upon evaporation of ether, the residue is subjected to fractional distillation in vacuo, thereby to yield 8.9 g. of N-methyl linseed oil fatty acid amide, B.P. 178-190° C./0.03 mm. Hg, I.R. 1,650 cm.-l. (I.R. means wave number of the infrared absorption spectrum.)... 

Shake for 1 minute, allow the layers to separate, and filter the chloroform extracts through separate filters of about 2 g of anhydrous granular sodium sulfate supported on pledgets of glass wool. Extract each aqueous layer with two additional 10 mL portions of chloroform, filtering and combining with the respective main extracts. Evaporate the chloroform solutions under reduced pressure to dryness, and dissolve each residue in 10 mL of carbon disulfide. The infrared absorption spectrum, determined in a 1-mm cell, of the solution obtained from the test specimen exhibits maxima only at the same wavelengths as that of the solution obtained from the Reference Standard (RS). 

Then 500 ml. of distilled water is added and the mixture boiled for 1-2 hours to destroy excess acetic anhydride and peroxides and to remove most of the methylene chloride. The solid which separates is collected after cooling and dissolved in the combined ethereal extracts (3 x 100 ml.) from the supernatant aqueous phase. The etheral solution is washed with 5% sodium carbonate solution, water, and brine, and dried over anhydrous sodium sulfate. Evaporation of the solvent yielded 87-96 g. (80-88.5%) of crude lactone, m.p. 87-89.5°. Two crystallizations from 95% ethanol afforded 78.5-86.2 g. (73.5-80%) of fine white crystals, m.p. 93.0-94.0°. The infrared spectrum exhibited peaks at 5.78 /a (0=0), 7.65 fi and 8.60 (C—O—C). The NMR spectrum (CD,), SO (TMS internal standard at 100 MHz) showed a characteristic aromatic multiplet at 5.4-6.6 (8 H). 

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... 

Thiophenes from alkynes 48 The alkyne is dissolved in methanol, ethanol, or acetone and the solution is adjusted to pH 9-10 by adding N-sodium hydroxide solution in the proportion 9 1. Hydrogen sulfide is then led in at 20-80° until a sample of the mixture no longer shows acetylene bands in its UV spectrum (4-20 h). The mixture is then treated with water, and the product is taken up in ether, dried over sodium sulfate, freed from solvent, and distilled or recrystallized. Thus were prepared 2,5-dimethylthiophene, b.p. 134-136° (70%), 2,5-dlethyl-thiophene, b.p. 180-181° (65%), and 2,5-diphenylthiophene, m.p. 152-153° (85%). 

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