Toluene evaporation

Carbazole-9-carbonyl chloride [73500-82-0J M 300.0, m 100-103 , 103.5-104.5 . Recrystd from C6H6. If it is not very pure (presence of OH or NH bands in the IR) dissolve in pyridine, shake with phosgene in toluene, evaporate and recrystallise the residue. Carry out this experiment in a good fume cupboard as COCI2 is very TOXIC, and store the product in the dark. It is moisture sensitive. The amide has m 246.5-247 , and the dimethylaminoethylamide hydrochloride has m 197-198 . [Weston et al. J Am Chem Soc IS 4006 1953.]... 

Occupational air Air collected/derivatized through 9-(A/-methylaminomethyl)anthracene in toluene evaporation HPLC with UV or fluorescence detection 0.1 g/m No data Sangd and Zimerson 1980... 

Occupational air air collected in mini-impinger containing nitro reagent in toluene evaporation HPLC with UV detection 1.5ppbfor20L air No data Dunlap et al. 1976... 

Air (HDI and oligomers) Air collected/derivatized through 1-(2-pyridyl)-piperazine in toluene evaporation HPLC with UV detection 0.7 g/m for 10 L air No data Goldberg et al. 1981... 

Merck) and toluene as the elutant. Dissolve the residue in the minimum volume of warm toluene (add a little dichloromethane if necessary) and elute the column with toluene. Evaporate the toluene eluates on a rotary evaporator to yield a residue which may be recrystallised from chloro-form/hexane (1 2, v/v c. 80 mL) to give the product diamine as colourless needles, m.p. 78-9°C, 4 g, 94%. 

HPLC is less commonly used by laboratories performing hair tests. HPLC with fluorescence detection has been evaluated by Marigo et al." Following LLE, extracts were derivatized with a solution of dansyl chloride. The derivatized extract was back-extracted into toluene, evaporated, and reconstituted in chromatographic eluent. The limit of detection was <1 ng/mg. Also, HPLC with coulometric detection was evaluated by Kintz for the analysis of buprenorphine. The detection limits were about 0.01 and 0.02 ng/mg for buprenorphine and norbuprenorphine, respectively. 

To a solution of 6-chloro-9-methylpurine (3 g, 18 mmol) in toluene (75 mL) was added AgF (21 g, 165 mmol), and the mixture was stirred and refluxed for 1.5 h. The silver salts were filtered and the toluene evaporated. Recrystallization (benzene/heptane, 1 1) gave needles yield 1,4g (52%) mp 125- 127 C. 

Sample preparation 0.5-1 mL Plasma + 500 jxL 4-8 p,g/mL IS in water + 500 p,L buffer + 4 mL dichloromethane n-propanol 99 1, extract on a rotamixer, centrifuge at 1200 g. Remove the organic layer and evaporate it to dryness under a stream of air at 30°, add 5 drops toluene, evaporate to dryness under a stream of air at 30°, reconstitute the residue in 200 p,L 50 mM triethylamine in MeCN, add 100 p,L 60 mM ethyl chloroformate in MeCN, after 30 s add 100 pL 1 M 1-leucinamide hydrochloride in MeOH containing 1 M triethylamine, after 2 min add 500 pL 250 mM HCl, extract with 4 mL ethyl acetate. Evaporate the organic layer to dryness under a stream of air at 30°, reconstitute the residue with 100 pL MeCN, add 400 pL 10 mM pH 6.5 phosphate buffer, inject a 60 pL aliquot. (Prepare buffer as follows. Neutralize a 1 M solution of tetrabutylammonium sulfate in water with NaOH, wash 5 times with dichloromethane, wash twice with heptane. Prepare a 100 mM pH 9.6 sodium carbonate buffer containing 0.5 M of the neutralized and washed tetrabutylammonium salt.)... 

Sample preparation Mix 300 pL of a 30 pM solution in dichloromethane with 10 pL 20 mM l-(6-methoxy-2-naphthyl)ethyl isothiocyanate in anhydrous dichloromethane and 50 pL 0.1% triethylamine in dichloromethane, vortex thoroughly, heat at 50° for 1.5 h, inject an aliquot. (Synthesize l-(6-metho -2-naphthyl)ethyl isothiocyanate as follows (protect from light). Dissolve 500 mg (S)-(+)-naproxen in 50 mL dry toluene, slowly add 5 mL freshly distilled thionyl chloride, reflux for 1 h, evaporate to dryness under vacuum, dry the acyl chloride (mp 87.5°) under vacuum over KOH for 2 days. Dissolve 0.5 mmoles acyl chloride in 5 mL acetone, stir at 0°, add 0.6 mmoles sodium azide dissolved in ice water, stir at 0° for 30 min, add 10 mL ice-cold water, filter, dry solid in a desiccator under vacuum. Dissolve the solid in 1 mL toluene or dichloromethane (dried over 3 A molecular sieve), reflux for 10 min, evaporate, store resulting isocyanate (mp 51°) under vacuum over a desiccant. Dissolve 0.5 mmole isocyanate in 5 mL acetone, add 20 mL 8.5% phosphoric acid, heat to 80° for 1.5 h, adjust to pH 13, extract with diethyl ether dichloromethane 4 1. Wash the organic layer twice with water, dry over anhydrous sodium sulfate, evaporate to dryness, dissolve in 1 mL toluene, evaporate to give the amine from... 

A thin layer chromatographic (TLC) system suitable for determination of clofazimine in plasma has been developed (Lanyi and Dubois, 1982). The plasma samples were acidified using acetate buffer pH 5 and extracted with toluene, evaporated to dryness under nitrogen, reconstituted in toluene and applied to the TLC plate. The adsorbent used was HPTLC silica gel 60. The plates were developed in toluene - acetic acid - water (50 50 4), allowed to stand for 30 min at room temperature, the Rf value of clofazimine was 0.36. Detection and quantitation is carried out using a densitometric method. The limit of detection reported for this method was 5ng/g. 

A thin toluene solution of metal nanoparticles and polystyrene (1 1 in weight) was evaporated on a clean glass plate at room temperature (299 K). The glass was kept vertically (70 degrees) till toluene evaporated completely. 

A first deposit was carried out by toluene evaporation on a flat made of AISI52100 polished mirror. The flat was heated to allow a faster evaporation of solvent. 

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