Pentafluorobenzyl hydroxylamine

B o-(2,3,4,5,6-Pentafluorobenzyl)hydroxylamine LLE GC Method (Disinfection By-Products Aldehydes)... 

Chemicals. The carbonyl compound standards 2-methylpropanal, 2-methylbutanal, 3-methylbutanal, pentanal, hexanal, furfural, methional, phenylacetaldehyde, and (E)-2-nonenal were purchased from Sigma-Aldrich (Milwaukee, Wl). A stock solution containing a mixture of the standard compounds in ethanol was prepared daily in a concentration of 100 ppb each. An aqueous solution of the derivatization agent 0-(2,3,4,5,6-pentafluorobenzyl)-hydroxylamine (PFBOA) (Sigma-Aldrich, Milwaukee, WI) was prepared at a concentration of 6 g/L. PFBOA solution was prepared every 3 months and kept refrigerated. 

The derivatizing agent 0-(2,3,4,5,6-pentafluorobenzyl)-hydroxylamine (PFBOA) was absorbed onto a 65 pm PDMS/DVB SPME fiber (10 min, 50 °C). 

An aqueous solution of the derivatization agent 0-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine was prepared at a concentration of 6 g/L. The PFBOA solution was prepared every 3 months. (Adapted from Vesely et ah, 2003)... 

Finally, formation of 0-(2,3,4,5,6-pentafluorobenzyl)-hydroxylamine (PFBOA) derivatives and analysis by GC-Mass Spectrometry (GC-MS) and GC-Electron-Capture Detection (GC-ECD) appears to be a promising technique, de Revel and Bertrand (42, 43) used PFBOA derivatization to analyze a number of saturated and unsaturated aldehydes in wines, however, high concentrations of acetaldehyde made accurate quantitation of the other aldehydes present in lower concentrations difficult, depending on the wine matrix the aldehydes were not always well separated from other chromatographic peaks pH conditions for the derivatization were not specified and removal of excess PFBOA by acidification caused the partial loss of some aldehydes. In addition, no specific information regarding derivatization efficiency and recovery, or absolute limits of detection and quantitation were reported by these authors. 

Pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA) [57981-02-9] M 249.6, m 215 , 215-216 , pKgst 1.1. Recrystd from EtOH to form colourless leaflets. Drying the compound at high vacuum and elevated temperature will result in losses by sublimation. [Youngdale J Pharm Sci 65 625 7976 Wehner and Handke J Chromatog 177 237 7979 Nambara et al. give incorrect m as 115-... 

Figure 1.19 Mass spectra of acetaldehyde PFB-oxime (a), diacetyl mono PFB-oxime (b), acetoin PFB-oxime derivative (c), and o-chlorobenzaldehyde PFB-oxime (d) recorded in the GC/MS analysis of standard solution performed in positive ion chemical ionization mode using methane as reagent gas (reagent gas flow 1 mL/min ion source temperature 200 °C). Flamini et al., (2005) Monitoring of the principal carbonyl compounds involved in malolactic fermentation of wine by synthesis of 0-(2,3,4,5,6-pentafluorobenzyl) hydroxylamine derivatives and solid-phase-microextraction positive-ion-chemical-ionization mass spectrometry analysis, Journal of Mass Spectrometry, 40, p. 1561. Copyright John Wiley Sons, Ltd. Reproduced with permission...

The RF calculated as average of glyoxal and 2,3-butanedione response factors. (From Rivista di Viticultura e di Enologia 2005 (1), Flamini et al., Study of carbonyl compounds in some Italian marc distillate (grappa) samples by synthesis of 0-(2,3,4,5,6-pentafluorobenzyl)-hydroxylamine derivatives, p. 56). 

For the GC method, 0-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine can be detected by flame ionization detector, MS/SIM detector, electron-capture detector, or flame photometric detector. 1,2-Diaminobenzene derivatives of MG can be analyzed using a flame ionization detector, MS/SlM, or a specific nitrogen/phosphorus... 

Methylation with diazomethane is rarely apphed as the only derivatization step to short-chain organic acids.It is, however, used in combination with o-(2,3,4,5,6-pentafluorobenzyl)-hydroxylamine (PFBHA) for ketoacids (see below). Once diazomethane has been generated, it is added to the extract which can then be injected in the GC, thus making this reagent rather convenient. Heating of the sample mixture is not required since the reaction takes place at low temperatures. The major disadvantages of diazomethane are its hazardous and explosive nature, and the necessity to generate it before it can be applied. ... 

Pentafluorobenzyl hydroxylamine has been used as a derivatization reagent in the analysis of corticosteroids including prednisolone by gas chromatography-negative ion chemical ionization mass spectrometry (NCI). The resulting... 

Formation of carbamate derivatives using pentafluorobenzyl-hydroxylamine hydrochloride... 

I,2,3,4,5,6)- Pentafluorobenzyl- hydroxylamine hydrochloride 2.16.2 Derivatization of steroids [26] and other ketones for ECD-GLC analysis and mass spectrometry Convenient fluorine-introducing alkylation for ketones... 

O-Ethyl hydroxylamine (HCl) O-Pentafluorobenzyl hydroxylamine hydroxylamine (HCl) (PFBHA) Hydroxylamine (HCl) (with following silylation of oximes) Methanol/H+... 

Li, N. Deng, C. Yao, N. Shen, X. and Zhang, X. Determination of acetone, hexanal and heptanal in blood samples by derivatization with pentafluorobenzyl hydroxylamine followed by headspace single drop microextraction and gas diromatography-mass spectrometry. Analytica Chimica Acta 2005, 540 (2), 317-323. 

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