Saturated Chloroform

Poly(7-benzyl-L-glutamate) is known to possess a helical structure in certain solvents. As part of an investigationf of this molecule, a fractionated sample was examined in chloroform (CHCI3) and chloroform saturated ( 0.5%) with dimethyl formamide (DMF). The following results were obtained ... 

The diester 226 undergoes ring-closure to the methylenecyclopentane derivative 227 in the presence of a catalytic amount of chlorotris(triphenylphosphine)rhodium in boiling chloroform saturated with hydrogen chloride. In contrast, if the reaction is catalysed by palladium(II) acetate, the isomeric cyclopentene 228 is produced (equation 115)118. 

Fig. 24 SFM phase images of surface structures in SB films, which were equilibrated under 70% of the chloroform-saturated atmosphere, showing specific neck defects (a) highlighted by dashed circles, interaction of neck-defects with m-dislocations (b, c), and with a single PL ring (d). Reprinted from [36], with permission. Copyright 2008 American Chemical Society...

Microcrystalline cellulose on TLC plates 0.1M EDTA with 0.1% NH4C1 166, 167 chloroform saturated with EDTA-NH4CI solution TC 72 ATC 36 EATC.-52 ... 

Colloidal Ice.—Ice can readily be obtained as an organosol by rapidly cooling saturated solutions of water in organic media. When, for example, chloroform, saturated with water, is rapidly cooled to —30° C., the ice separates out in particles of colloid dimensions, and the sol may be passed unchanged through filter paper.5... 

Fig. 3. Intrinsic viscosity-molecular weight relationship of poly-7-benzyl-L-glutamates. The open circles represent the randomly coiled form and other symbols the a-helical form. The line of steeper slope is a plot of Simha s equation. Abbreviations dichloroacetic acid, DCA chloroform saturated with formamide, C-F dimethyl formamide, DMF light scattering, L.S. weight-average molecular weight, A/m. Reproduced from Doty et al. (1956).

A silica gel Si 100 (10cm x 4.6mm) Chloroform saturated with picric acid (0.35 ml min-1) UV Identification and (142) quantitation of hyoscyamine which was separa-... 

Chloroform saturated with the buffer. (The picrate ion-pair of alkaloids were injected as solutions in CHCI3)... 

Column Silica gel SilOO 5 pm (100x3 mm ID) impregnated with 0.06 M picric acid (pH 6), mobile phase chloroform saturated with the stationary phase 0.06 M picric acid, flow rate 0.2 ml/min, detection UV 345 nm. Peaks 1, dodecylbenzene (t ) 2, apoatropine 3, ergotaminine 4, atropine 5, ergotamine 6, scopolamine. 

The higher order grating signal after the photoexcitation of all-trans-f -carotene (Fig. 21) was interpreted by a two-step absorption model [117], By simultaneous fitting of the first- and second-order diffraction intensity versus the excitation intensity, the quantum yield of the photoisomerization (iso) and the kinetic parameters were determined. The results showed distinct solvent dependence. In hexane, the effect of 0iso was very small and the upper limit was obtained as 7 x 10-4. The nonlinear absorption in this case was caused by the excited absorption. In chloroform, saturation was observed in the absorption and it was attributed to formation of a trap state, most likely a photoisomer. By the fitting, (f>iso was obtained as 0.026 and the kinetic parameter and cross section of subsequent photoisomer absorption were determined. 

Hyoscyamine, scopolamine and ergotamine in pharmaceutical products Ion-pair chromatography LiChrosorb SI 100 loaded with 0.06M picric acid in pE16 buffer Chloroform saturated with 0.06M picric acid in buffer pE16. 

Sample preparation Grind tablets to a fine powder and add about 250 mg aspirin to 100 mL chloroform saturated with citric acid containing 500 p,L formic acid, add 500 mg solid citric acid, sonicate for 2 min, centrifuge or filter, inject an aliquot. (If buffers or antacid are present, add ground tablets equivalent to about 500 mg aspirin to 3 g acid-washed siliceous earth, mix, add 2 mL 6 M HCl, mix, add to a 200 X 25 column, dry wash... 

Cleavage of ketals. Dimethyl and diethyl ketals are converted into ketones in 85-95% yield by treatment with iodotrimethylsilane in chloroform saturated with propene, added to eliminate traces of HI in the reagent. Ethylene ketals also react, but give a complex mixture of products. Thioketals are completely stable. The probable mechanism is shown in equation (I). 

Chromatographic purity of amodiaquine hydrochloride can be examined on thin-layer plate coated with a 0.2S mm layer of silica gel G using solvent system chloroform (saturated with ammonium hydroxide) dehydrated alcohol (9 1). Under short-wavelength ultraviolet light, the chromatogram shows principal spot at about the same Rf value, and no secondary spot, as obtained with the USP Amodiaquine Hydrochloride RS (10). 

Deketalization can be accomplished using iodotrimethylsilane in chloroform saturated with propene the alkene is required to trap traces of HI present. ... 

D19. Many extraction systems are partially miscible at high concentrations of solute, but close to immiscible at low solute concentrations. At relatively low solute concentrations both the McCabe-Thiele and trianglar diagram analyses are applicable. This problem explores this. We wish to use chloroform to extract acetone from water. Equilibrium data are given in Table 13-4. Find the number of equilibrium stages required for a countercurrent cascade if we have a feed of 1000.0 kg/h of a 10.0 wt % acetone, 90.0 wt % water mixture. The solvent used is chloroform saturated with water (no acetone). Flow rate of stream Eq = 1371 k. We desire an outlet raffinate concentration of 0.50 wt % acetone. Assume immiscibility and use a weight ratio units graphical analysis. Conpare results with Problem 13.D43. 

Mistryxjkov [18] has chromatographed fmrw-decahydroqiiinoline, as-deca-hydroquinoline, (l)-cw-perhydropyridine, their derivatives and some aromatic amines he used loose alumina layers and various neutral or basic solvents such as acetone-methanol-water (72 + 18 + 9) and chloroform (saturated with ammonia)-benzene (50 + 50). 

Operating conditions Solid and liquid samples were dissolved in benzene, carbon tetrachloride or chloroform. Neat liquid ferrocene could also be injected directly without dilution into the flash vapourizer by means of a microsyringe. Chloroform was the best solvent for most of the compounds, although the hydroxymethyl-substituted ferrocenes were more soluble in benzene than in chloroform. Saturated or nearly saturated solutions were used in most instances, and sample sizes ranged from 0.1 to 10 yl. 

Continental Waters. Some data have recently been obtained for Central Kazakstan (Table 25) on waters in cracks and sediments of Devonian volcanics and sediments and water from the Sea of Azov and Lake Balkash (Andreyev et al, 1967). In this difficult analitical problem, the lead was collected either (1) on activated charcoal saturated with chloroform saturated with dithizone or (2) as a coprecipitate with a tannin-gelatin complex. The transient water was found to be highly variable in lead isotope ratios, both radiogenic and non-radiogenic and the lake waters had about the same ratios as oceanic manganese nodules or were less radiogenic. 

Polymerization of phenylalanine catalyzed by a-chymotry in-poly(ethylene glycol) complex was examined [48]. The solvent used is chloroform saturated by Tris buffer (pH 7). The monomer conversion was 72% giving the dimer and then the hexamer. 

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