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General procedure for solution

General Procedure for Solution-Spray Flash Vacuum Pyrolysis (SS-FVP)... [Pg.466]

General Procedure for Solution Polymerization of Dibasic Thioacids and Biallyl.. . 49... [Pg.46]

Alkvl Azides from Alkyl Bromides and Sodium Azide General procedure for the synthesis of alkyl azides. In a typical experiment, benzyl bromide (360 mg, 2.1 mmol) in petroleum ether (3 mL) and sodium azide (180 mg, 2.76 mmol) in water (3 mL) are admixed in a round-bottomed flask. To this stirred solution, pillared clay (100 mg) is added and the reaction mixture is refluxed with constant stirring at 90-100 C until all the starting material is consumed, as obsen/ed by thin layer chromatographv using pure hexane as solvent. The reaction is quenched with water and the product extracted into ether. The ether extracts are washed with water and the organic layer dried over sodium sulfate. The removal of solvent under reduced pressure affords the pure alkyl azides as confirmed by the spectral analysis. ... [Pg.156]

As with a pH meter, the electrode appropriate to the measurement to be undertaken must be calibrated in solutions of known concentration of the chosen ion at least two reference solutions should be used, differing in concentration by 2-5 units of pM according to the particular determination to be made. The general procedure for carrying out a determination with one of these instruments is outlined in Section 15.16. [Pg.567]

The general procedure for performing a potentiometric titration with non-aqueous solutions is in essence the same as that employed for aqueous solutions, but there are some important points of difference. [Pg.589]

The reaction was carried out analogously to the general procedure for the addition of metalated ally 1 sulfoxides given in Section 1.5.2.2.3.2. BuL.i is used, in this case, for deprotonation instead of LDA. BuLi is added to a solution of 1 - 3 mmol of the phosphine oxide or phosphonate in THF until the first permanent appearance of the red color of the anion. Thereupon, 1.1 equivalents of the BuLi is added. For the phosphonates, whose anions are less intensely colored, 1.1 equivalents of BuLi are added to the solutions after the first permanent appearance of the red color of an added indicator, 2.2 -bipyridyl. [Pg.918]

Oxidation of phenyl hexyl sulphide with sodium metaperiodate gave also only a trace amount of the corresponding sulphoxide72. On the other hand, Hall and coworkers73 prepared benzylpenicillin and phenoxymethyl penicillin sulphoxides from the corresponding benzyl esters by oxidation with sodium metaperiodate in dioxane solution with a phosphate buffer. A general procedure for the synthesis of penicillin sulphoxides was reported later by Essery and coworkers74 which consists in the direct oxidation of penicillins or their salts with sodium metaperiodate in aqueous solution at pH 6.5-7.0. 1-Butadienyl phenyl sulphoxide 4475 and a-phosphoryl sulphoxides 4576 were also prepared by the same procedure. [Pg.246]

The general procedure for the preparation of vanadium borates consists in heating a concentrated H2O solution of boric acid and vanadium oxide in an autoclave at 170 °C for several days [143]. Two different vanadium borate clusters 105 and 106 are obtained, one with two polyborate chains coordinated to a contorted vanadium oxide ring (105) and another one with a macrocyclic Bi8036(0H)6 ring (106). The latter ring is composed of six B306(0H) units and has a chair-like conformation (Fig. 27) [143]. [Pg.29]

General Procedures for the Synthesis of the Pyridone Sulfonates VIa,b,c and VIIa,b,c (25). A solution of 1.25 mmol of the sodium salt of 3-carbamoyl-2(lH)pyridone(III) or 3-phenyl-2(lH)pyridone and 1.25 mmol of the corresponding bromosulfonate sodium salt in 50 mL of acetonitrile was brought to reflux and stirred for 24 h. The reaction mixture was cooled and filtered through a sintered glass... [Pg.225]

General procedures for the synthesis of ligands and metal complexes are shown in Scheme 1. For file synthesis of 2a acenaphthenequinone (0.38 g, 2.1 mmol) and a,a-bis(4-amino-3,5-dimethylphenyl)-toluene(Kccess) were dissolved in 50 mL of CH3OH in a round-bottom flask. Five drops of formic acid were added, and the sealed solution was stirred at 50 C overnight. After filtration, the red solid was washed with hot methanol and dried to give 1.2 g of red powder in 50 % yield. [Pg.857]

In the laboratory, a solution of known concentration is often prepared in a glass vessel called a volumetric flask. Volumetric flasks typically allow volumes to be measured with an accuracy of four significant figures. Figure 3-17 summarizes the general procedure for making a solution in a volumetric flask. This procedure is further described in Example 3-17. [Pg.170]

General procedure for Suzuki coupling. 4-Bromoanisole (125 pL, 1 mmol), phenylboronic acid (186 mg, 1.5 mmol), K2CO3 (0.55 g, 4 mmol) and the BaCei.j,Pdj,03.j, catalyst were mixed in a 20 ruL scintillation vial. A preheated 2-propanol/water solution (IPA/H2O, 1 1 v/v, 12 ruL, 80°C) was added, the vial was immediately placed on a hot plate stirrer and its temperature was maintained at (80 1) °C. The reaction mixture was stirred at 1000 rpm for 3 min, then cooled to room temperature. The 4-methoxybiphenyl product was extracted with diethyl ether (3 x 15 ruL). The organic fractions were washed with deionized water and dried with MgS04. After filtration, volatiles were removed under reduced pressure to yield the isolated product. [Pg.234]

General procedure for the production of Boc-protected a,a-diaryl-L-prolinols (6). To 100 mL of a 0.42 M solution of ArMgBr in THF (0.042 mol) at 0°C was added N- t- BOC)-L-proline methyl ester (5) (3.0 mL, 0.014 mol) dropwise via syringe over a five-minute period. The solution was stirred for at least 4 h at 25°C and then cooled to 0°C. After slow addition of 3 mL of water, the solution was slowly warmed to ft with stirring. The mixture was decanted and the solid was washed with 100 mL of ethyl ether. The organics were pooled and washed with brine, dried with sodium sulfate and evaporated to yield the final compound. [Pg.494]

The following treatment has been suggested by Shiu et al. (1994) and is reproduced briefly below. The simplest, first-order approach is to take into account the effect of dissociation by deducing the ratio of ionic to non-ionic species I, the fraction ionic x and the fraction non-ionic xN for the chemical at both the pH and temperature of experimental data determination (/D, xID, xND) and at the pH and temperature of the desired environmental simulation (/E, xIE, xNE). It is assumed that dissociation takes place only in aqueous solution, not in air, organic carbon, octanol or lipid phases. Some ions and ion pairs are known to exist in the latter two phases, but there are insufficient data to justify a general procedure for estimating the quantities. No correction is made for the effect of cations other than H+. This approach must be regarded as merely a first correction for the dissociation effect. An accurate evaluation should preferably be based on experimental... [Pg.7]

Potter and co-workers 301) determined reducing sugars in plant materials by reducing copper(II) in alkaline solution to insoluble cuprous oxide and then measuring the excess copper in the filtrate. Mitschell248) conducted further studies on this method. Christian and Feldman 19) have described general procedures for the indirect determination of glucose and of protein. It is anticipated that in the future, we will see many more applications of atomic absorption spectroscopy to the indirect determination of nonmetals. [Pg.107]

General Procedure for the Formation of Benzene Derivatives (see Eq. 2.48) At 0°C, dimethyl acetylenedicarboxylate (284 mg, 2 mmol) and CuCl (198 mg, 2 mmol) were added to a solution of zirconacyclopentadiene (1 mmol) in THF, prepared in situ according to the known procedure [12]. The reaction mixture was then allowed to warm to room temperature and was stirred for 1 h. After hydrolysis with 3 n HC1, the mixture was extracted with diethyl ether. The combined extracts were washed sequentially with water, aq. NaHC03 solution, brine, and water, and then dried over MgS04. Concentration in vacuo followed by flash-chromatography eluting with a mixture of hexane and diethyl ether (10 %) afforded benzene derivatives. [Pg.82]

Another general procedure for effecting initial subdivision of the crude mixture of polysaccharides obtained on alkaline extraction is that of Schulze68 and O Dwyer62 which takes advantage of the fact that neutralization of the solution causes precipitation of the high molecular weight... [Pg.290]

General procedure for the preparation of 4-functionalized-l-alkyl-3-methylindoles (2) A solution of the starting amine 1 (2 mmol) in THF (15 mL) was treated with /BuLi (7 mmol, 3.5 equiv) at -110°C. The reaction mixture was stirred at this temperature for 15 min and then at -40°C for 3 h. The reaction mixture was re-cooled to -78°C and the electrophile (3 mmol) was added. The reaction mixture was stirred overnight at room temperature, then hydrolyzed with water, and extracted with ethyl acetate (3 x 20 mL). The combined organic layers were dried over anhydrous Na2S04. The solvent was removed under vacuum and the residue was purified by flash column chromatography (hexane/ethyl acetate) and/or by recrystallization to afford products 2. [Pg.7]

General procedure for the preparation of 4-functionalized 3-methylindoles (3) A solution of the starting amine lb (2 mmol) in THF (15 mL) was... [Pg.8]


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General procedures

General solution

Solution Procedure

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