3- Methylpentan-2-one

Methylpentan-2-one 20 pmol 4-methylpentan-2-one/l in urine (HGV) Post shift... 

The solution was then heated at reflux for A hour, cooled to 70°C and 4-methylpentan-2-one (2 liters) added. The water was removed by azeotropic distillation under reduced pressure (260 torrs) and the resultant solution treated with charcoal (10 g) at 50°C. The solution was filtered and cooled to 10°C. N-[2-[ [ [5-dimethylamino)methyl-2-furanyl] methyl] thio] ethyl] -N -methyl-2-nitro-1,1 -ethenediamine (380 g) was filtered off and dried, melting point 69°C to 70°C. 

Solutions in organic solvents may, with certain reservations, be used directly, provided that the viscosity of the solution is not very different from that of an aqueous solution. The important consideration is that the solvent should not lead to any disturbance of the flame an extreme example of this is carbon tetrachloride, which may extinguish an air-acetylene flame. In many cases, suitable organic solvents [e.g. 4-methylpentan-2-one (methyl isobutyl ketone) and the hydrocarbon mixture sold as white spirit ] give enhanced production of ground-state gaseous atoms and lead to about three times the sensitivity... 

Lead caprate. Prepare a standard stock solution by dissolving 0.1323 g of the solid in 2 mL of naphthenic acid with warming. Add 20 mL of 4-methylpentan-2-one (methyl isobutyl ketone), cool and then make up to the mark in a 100 mL graduated flask with more of the ketone. 

Transfer the solution to a 250 mL separatory funnel, rinsing out the beaker with a little water. Add 5 mL of the 2 per cent NaDDC reagent and allow to stand for one minute, and then add a lOmL portion of 4-methylpentan-2-one (methyl isobutyl ketone), shake for one minute and then separate and collect the organic layer. Return the aqueous phase to the funnel, extract with a further lOmL portion of methyl isobutyl ketone, separate and combine the organic layer with that already collected. Finally, rinse the funnel with a little fresh ketone and add this rinse liquid to the organic extract. In these operations the lead is converted into a chelate which is extracted into the organic solvent. 

In the malachite green procedure, 10 ml of the sample solution containing up to 0.7 xg phosphorus as orthophosphate was transferred into a 25 ml test tube. To this solution was added 1 ml each of 4.5 M sulfuric acid and the reagent solution. The solution was shaken with 5 ml of a 1 3 v/v mixture of toluene and 4-methylpentan-2-one for 5 min. After phase separation, the absorbance of the organic phase was measured at 630 nm against a reagent blank in 1 cm cells. 

Moffett [179] determined chromium in seawater by Zeeman corrected graphite tube atomisation atomic absorption spectrometry. The chromium is first complexed with a pentan-2,4 dione solution of ammonium 1 pyrrolidine carbodithioc acid, then this complex extracted from the water with a ketonic solvent such as methyl isobutyl ketone, 4-methylpentan-2-one or diisobutyl ketone. 

Synonyms AI3-00045 BRN 1740440 Caswell No. 280 CCRIS 6177 DAA Diacetone Di-acetonyl alcohol Diketone alcohol Dimethylacetonyl carbinol EPA pesticide chemical code 033901 4-Hydroxy-2-keto-4-methylpentane 4-Hydroxy-4-methylpentanone-2 4-Hydroxy-4-methylpentan-2-one 4-Hydrojg -4-methyl-2-pentanone 2-Methyl-2-pentanol-4-one NSC 9005 Pyranton Pyranton A Tyranton UN 1148. 

Hydroxymethylfuran, see Furfuryl alcohol 2-Hydroxymethyloxiran, see Glycidol 4-Hydroxy-4-methylpentanone-2, see Diacetone alcohol 4-Hydroxy-4-methylpentan-2-one, see Diacetone alcohol 4-Hydroxy-4-methyl-2-pentanone, see Diacetone alcohol... 

Each sample was then mixed with a solution of APDC and the samples were then extracted with 10 ml 4-methylpentan-2-one. The organic layer was then separated and was then analysed by AAS. 

Tominaga, T. and D. Dubourdieu. 1997. Identification of 4-mercapto-4-methylpentan-2-one from the box tree (Buxus sempervirens L.) and broom (Sarothamnus scoparius (L.) Koch.). Flavour and Fragrance J. 12 373-376. 

NiL,(C104)2 4-Hydroxy-4-methylpentan-2-one (diacetone alcohol) SqPl ligand formed by the condensation of two molecules of acetone 1500... 

Perfluoro ketones and perfluoro a-diketones, with a trifluoromethyl group in the -position to the carbonyl, cyclize in the presence of antimony(V) fluoride to give furan derivatives, as reviewed by Krcspan and Petrov.4 Perfluoro(4-methylpentan-2-one) (1) rearranges to per-fluoro(2,4-dimethyltetrahydrofuran) (2) in 84% yield, when heated in the presence of anti-mony(V) fluoride.5... 

Plot a graph of logi0f against the molecular weight or alternatively the carbon number (i.e. the number of carbon atoms in the molecule) of the ketone. Estimate the retention time of a ketone containing six carbon atoms and check your result by a suitable injection. Finally examine the chromatographic behaviour of 3-methylbutan-2-one, 4-methylpentan-2-one and 5-methylhexan-2-one. 

Ketones. Normal acyclic ketones can be recognised by a strong band at 1720 cm -1 (e.g. see the spectrum of 4-methylpentan-2-one, Fig. 3.28). Branching at the a-carbon atoms results in an increase in the C—CO—C bond angle and this results in a decrease in frequency of absorption from the normal value of 1720 cm -1 to, for example, 1697 cm -1 as in di-t-butylketone. Conversely as the C—CO—C bond angle is decreased the absorption frequency rises, thus cyclo-pentanone and cyclobutanone absorb at 1750 cm-1 and 1775 cm-1 respectively. 

Thus the spectrum of 4-methylpentan-2-one (Fig. 3.84) shows a strong peak at m/z due to the odd-electron ion (CH3C(OH)=CH2) resulting from the McLafferty rearrangement. 

A widely studied example of this kind is the synthesis of methyl isobutyl ketone (MIBK, used as a solvent for inks and lacquers) from acetone. The former was previously prepared from the latter through a catalytic three-step process base-catalysed production of 4-hydroxy-4-methylpentan-2-one, acid dehydration into mesityloxide (MO), then hydrogenation of MO on a Pd catalyst. Since acetone aldolization occurs through acid catalysis as shown over a H-MFI zeolite at 433 K (MO is the main reaction product, the aldolization product being rapidly dehy-drated[5]), it is possible, by associating with the acid catalyst a hydrogenation phase,... 

The detection limit for gallium determination at 287.4 nm in an air-acetylene flame is only about 70 ng ml - and that by flame AFS is not much better, and sometimes even worse.1 The detection limit by flame AES at 403.3 nm is appreciably better, especially if a nitrous oxide-acetylene flame is used. This reflects the low excitation energy. These values are too low to make the direct determinations useful in environmental applications, and therefore solvent extraction is often used for pre-concentration.1 One method often used is the extraction of the anionic keto-chloro complex from strong hydrochloric acid solution (e.g. 5.5M) into 4-methylpentan-2-one.25,26 Co-extraction of iron may... 

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